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Video/Graphics Cards: PCI - AGP - PCI Express - Page 1

This section of this website, combined with its Graphics Card Problems, Monitors and Laptop PCs sections, provides all of the information a prospective or an actual desktop and laptop PC owner needs to know about graphics cards and other graphics implementations and the problems that beset them. The information presented here on graphics cards for the desktop PC that use the PCI, AGP and PCI Express standards, which appeared in that order, is provided in two long pages, the first of which is the longest. The current motherboard standard used for internal video/graphics cards is PCI Express, but graphics cards are still available using the older PCI and AGP standards. External devices that provide graphics use the USB interface. Graphics chips built into processors, recently made available by AMD and Intel, are dealt with on this page. AMD calls its processors with onboard graphics Accelerated Processing Units (APUs). The trend towards ever-greater component integration continues. There is far too much information provided in this article to make providing a contents menu possible, but the contents have been presented in a way that makes scrolling down the page to gauge what is on offer a relatively easy matter. If you are looking for specific information on the two pages of this article, press the Ctrl + F key combination, which brings up the Find box in most browsers. It will only find the whole search query that you enter in it, not the individual words.


Click here!to visit the page on this site devoted to video/graphics problems and their solutions.


Click here!to go to information on this site on what you need to consider when upgrading a PC's video/graphics card.

An ATI Radeon X1300 PCI Express video card ATI Radeon HD 2400 PCI Express video/graphics card with a passive cooling

The video/graphics cards (also known as graphics accelerator cards) used in desktop PCs and laptop/notebook PCs contain the electronics that deliver the picture/display to the computer's monitor or monitors. Monitors, because it has been possible to connect many monitors to a desktop PC via multiple graphics cards (called multi-monitor, multi-display, dual-display, etc.) since 1987 using the Apple Mac OS operating system (on the first colour Macintosh II) and since 1998 in Windows with the introduction of Windows 98.

The computer's graphics display can now be provided by a dedicated graphics card or by a graphics chip integrated on the motheboard or on the processor itself. With AMD's A-Series APU processors, which have an integrated graphics chip, it is also possible to install an AMD Radeon graphics card which runs in CrossFire mode in conjunction with the processor's graphics chip to increase performance significantly. Nvidia equivalent dual-card mode is called SLI. Dedicated PC gamers prefer using a single powerful graphics card instead of these dual-card setups because they tend to be more problematic or glitchy.

Here are two interesting articles on AMD's CrossFire and Nvidia's SLI:

FX Vs. Core i7: Exploring CPU Bottlenecks And AMD CrossFire [January 2013] -,review-32616.html

Origin PC Millennium: 3-Way SLI And A 4.6 GHz Core i5 [December 2012] -,review-32590.html

To use a motherboard's or a processor's integrated graphics chip requires the motherboard to provide the graphics ports that matches the monitor or monitors graphics ports, which are now VGA (analog), and digital DVI, HDMI and DisplayPort input ports. Inexpensive adapters make it possible to use one standard with another, such as a VGA port on a laptop with a DVI-I or DVI-D port on the monitor.

If a graphics chip is built into the PC's motherboard or its processor, the graphics capability will usually be good enough to run office applications, use email programs, watch movies and web surfing, but seldom good enough to play the latest PC games at their full software settings for the hardware, of which anti-aliasing and the monitor's screen resolution are probably the most well-known.

The reason than many people buy high-end graphics cards is because they provide an unparalleled level of gaming performance. Here is an article on Tom's Hardware that provides information and benchmark-testing results for a demanding PC game tested on no fewer than 12 graphics cards.

Medal Of Honor Warfighter Performance, Benchmarked [2 Nov. 2012]-,review-32557.html

Note that some of Intel's first and second generation Core i3, i5 and i7 processors for the desktop and laptop PC have an onboard graphics chip that is usually used in entry-level PCs and workstations. With Intel's processors that provide onboard graphics, if you add a separate graphics card to beef-up the graphics power, you have to disable the graphics provided from the processor because it cannot be connected to a second monitor and so cannot provide graphics to the monitor at the same time as the graphics card.

AMD has released its A-series Fusion APU range of dual-core and quad-core processors to laptop manufacturers that provide onboard graphics. By mid-June 2011, HP had made laptops available with the new processor in the USA. This will extend to the rest of the world in the next few months. The versions of the Fusion APU processors for the desktop PC will follow shortly afterwards, which is a reversal of the usual order of release: desktop processors are usually released first. The most interesting specification is the ability of the onboard graphics chip of the Fusion APU processors to work in tandem with an AMD Radeon graphics card in CrossFireX mode, increasing graphics performance, which already outperform Intel's latest Core processors by about 60% in 3D mode.

The Fusion APU processors support the latest DirectX 11; Intel's Core processors with onboard graphics only support DirectX 10. The Fusion processors are capable of playing games; Intel's Core processors with onboard graphics can't play games without the aid of a separate graphics card. In tests, the battery life of the Fusion APU mobile (laptop) processors is much longer than Intel's mobile Core processors. The Fusion APU processors can be 29% slower in 2D mode than Intel's Core equivalent processors, but AMD stresses that only users that work with spreadsheets with 25,000 rows would benefit from the extra performance in 2D mode that Intel's processors provide.

The models for the desktop PC are: A6-3600, A6-3650, A6-3800 and A6-3850, all of which have an AMD HD 6550D graphics chip. The top of the range model - the A6-3850 - currently priced (August 2011) at only L100, plays Dirt 3 smoothly at 35fps on a monitor with a 1280x720 screen resolution using High detail settings and 4x anti-aliasing, which proves that it can play the latest games on its own. When a low-end AMD Radeon 6450 graphics card, currently costing around only L35, is added to the system so that it works in CrossFire mode with the graphics chip in the processor, the fps increases to 52. This processor, or APU as AMD calls it, is not as fast as Intel's Sandy Bridge second-generation Core processors when running 2D applications, but it is much faster when playing games, especially when running with a cheap low-end AMD graphics card, and is much cheaper.

The following excellent article on overclocking an AMD A-Series A8-3870K (first-generation Llano) APU, which can play the latest games without help from an additional graphics card, covers the overclocked components - the processor, memory and the additional Radeon HD 6670 graphics card. The beginning is a very informative interview with overclocking expert, Sami Mäkinen. The processor is tested on five platforms running the latest games.

Professional Help: Getting The Best Overclock From AMD's A8-3870K -,review-32499.html

If you want to know all about the graphics card/chip that is being used by your desktop or laptop PC, GPU-Z is a free utility that meets all of the needs of most home users:

Technical documentation - guides and user manuals - are usually provided as PDF downloads (requiring a PDF reader) from the graphics-card or motherboard manufacturer's website. The PDF downloads are usually 6MB+ in size, so can take a while to appear in your computer's PDF reader. Creative provides online user guides for its sound cards. An example is the Catalyst Control Center User Guide. The device drivers for AMD's Radeon graphics cards are called Catalyst drivers and the download installs the Catalyst Control Center that provides the settings and other options for the graphics card using the drivers.

Here is an example of the graphics-card information that it provides for an ATI Radeon HD 5800 Series PCI Express (PCI-E) graphics card:

The Graphics Card tab of the  GPU-Z utility that provides information on graphics cards

Most users only need to know the make/model, shown under Name (to be able to download its latest device drivers from the manufacturer's website), DirectX Support (Windows 7 requires a graphics card that supports a minimum of DirectX 9.0 - important if you are upgrading from an earlier version of Windows, such as Windows XP), the Bus Interface (PCI, AGP, PCI Express) and the Memory Size (1024MB = 1GB in this example). Note that ATI is now called AMD, having been purchased by AMD, which means that AMD and NVIDIA are now the two major manufacturers of graphics chips.

Every graphics card or graphics chip integrated on a desktop or laptop PC's motherboard installs a display control panel when its device drivers are installed that adds to the display options provided by Windows XP, Windows Vista and Windows 7. It will either be an independent control panel, usually added to the main Windows Control Panel, or be added to the Display Properties feature in Windows that is accessed from its main Control Panel.

For example, to access the graphics chip manufacturer's control panel in the laptop PC I'm using to write this, which has its graphics integrated on the motherboard instead of as a separate graphics card, I have to open Display in the Control Panel (Windows XP/Vista/7) or right-click an empty space on the Desktop and click Properties. In Windows 7 all you have to do is enter the word display in the Start => Search programs and files box to be presented with a link that opens it. With the Display Properties window on the screen, click the Settings tab to open it and then click the Advanced button. The image below is the window that I get. The top tab called Intel Graphics Media Accelerator Driver for Mobile gives access to the laptop's integrated Intel 945GM graphics control panel, which allows me to change the colour-correction settings - brightness, contrast, gamma.

Windows XP, Vista, Windows 7 Display Properties Settings => Advanced  window

The image below shows how the Intel 945GM graphics chip appears in the Windows Device Manager. Both entries are required because they provide different functions. To uninstall the graphics adapter, both entries have to be uninstalled. A double click opens the window showing each entry's information and options. A right-click on each entry allows you to update the driver and disable or uninstall the graphics adapter. If you uninstall the graphics adapter, Windows reinstalls the device drivers the next time the computer starts up or is restarted. Just doing that fixes many graphics problems. Alternatively, you can download and install the latest drivers from the display-adapter manufacturer's website.

The Windows Device Manager  showing the Dislay adapters

The control panel of a separate graphics card, now mostly installed in a PCI Express x16 slot on the motherboard, usually provides several more control settings and and sometimes even troubleshooting options. The image below shows the Catalyst Control Center for an ATI Radeon graphics card. A high-end graphics card has its own memory and fan to keep the main GPU chip cool, which a graphics chip integrated into the motherboard of a desktop or laptop PC does not usually have, hence the options for memory-clock settings and fan control.

ATI Radeon graphics card's Catalyst Control Center

The number of graphics cards that can be connected to a PC depends on the number of graphics cards installed in it. The highest-end graphics cards currently available can support three monitors each that show an independent (different) display. Theoretically, an infinite number of monitors that are displaying the same display can be connected using distribution amplifier boxes to send the signal from the computer to each monitor.

High-end PCI Express video/graphics cards have to be connected directly to the power supply unit (PSU). The image below shows where the two 6-pin PCI Express (PCI-E) power connectors from the power supply are connected on an AMD Radeon HD 6790 graphics card.

Where two PCI Express power connectors from the PC's power supply power are connected  on an AMD Radeon HD  6790 graphics card

Note that all AMD's and NVIDIA's high-end graphics cards are now double-slot cards that are twice as thick as a single-slot card, which means that although installed in only one slot, they require the space of two PCI Express slots.

Also note that if you have a small case, you should measure the space available to a particular graphics card before buying it. The specifications of all graphics cards, including their length and height, are provided from the manufacturer's website. If a card's length or height exceeds the available space, it cannot be installed. Low-profile cards, designed for small cases, have half the height of standard-sized cards.

Also note that all the most powerful high-end graphics cards require one or more 6-pin or 8-pin PCI Express power connectors provided by the power supply unit as an auxiliary source of power. Standard Molex power connectors on a power supply unit (PSU) can be adapted to the 6-pin and 8-pin power connectors by using an adapter cable costing around L3 or less. You can now buy and adapter that uses two Molex connectors to produce a single 8-pin PCI Express power adapter. Web-search: Dual Molex LP4 4 pin to 8 pin PCI-E Express Converter Adapter Power Cable - only 99 pence in the UK on Amazon.

The following website shows examples of PCI Express power connectors.

If a particular power supply unit doesn't have the required number of PCI Express connectors, it's possible to buy an adapter that is fitted to a standard Molex power connector of the kind that fits to standard IDE ATA (non-SATA) disk drives that changes it into one.

There are now four graphics-display standards in use - VGA, DVI, HDMI (high-definition) and DisplayPort. DisplayPort comes in a standard version and as the Mini DisplayPort version, which can be converted to standard DisplayPort with an adapter designed for that purpose. All of those standards are digital except VGA which is an analog standard. DVI-I output ports of the DVI standard can carry both analog VGA and digital DVI video, but DVI-D ports of the DVI standard can only carry digital video.

The image shown below of a PCI Express AMD Radeon HD 6450 graphics card has digital DVI-D (right), DisplayPort (middle) and analog VGA (blue, left) output ports. A DVI-D output port can use a DVI-to-HDMI converter for 3D display over an HDMI 1.4a connection, which all new HD TVs provide. You'll note that a DVI-D port shown below in the image of an AMD Radeon HD 6950 graphics card does not have the four extra analog VGA pins provided by a DVI-I port (shown in the image of the face plate of a graphics card with a white DVI-I port immediately below it) that can connect it to a monitor's VGA input port via a supporting cable.

A PCI Express AMD Radeon HD 6450 graphics card with digital DVI-D, DisplayPort and analog VGA output ports Close up of the DVI and D-sub ports on a video/graphics card

A single-link DVI cable can handle screen resolutions up to 1920X1200 pixels, but a dual-link cable is required for screen resolutions above that up to 2560x1600 pixels, which makes DVI the most complicated graphics standard by far. DVI can be converted to HDMI or DisplayPort (the DisplayPort graphics standard was designed to replace the analog VGA and digital DVI standards).

The full-sized and Mini variation of DisplayPort is growing in popularity as a means of connecting high-resolution monitors to desktop and laptop PCs.

An HDMI port on a graphics card, TV or monitor can also be connected to a DisplayPort on a graphics card, TV or monitor by making use of an all-in-one HDMI-to-DisplayPort cable. The digital HDMI standard carries sound and audio for modern PC monitors, TVs and home amplifiers. It can be converted to DVI with a suitable adapter cable, but with the loss of sound, which can be made good by connecting the device to the PC's sound card with a suitable connection cable.

In July 2011, the company responsible for governing the HDMI standard has decreed that adapter cables for converting an HDMI port to a Mini DisplayPort are not covered under existing licences and therefore must not be sold. Fortunately, it is still legal to use a dongle that accepts an HDMI cable as an input which has a DisplayPort connector. This means that instead of using a single cable, two cables are required to achieve the same connection - an HDMI cable and the dongle. Heads obviously need smashing together over this silliness. If you want to connect an HDMI port to a DisplayPort with a single cable, you'll have to buy one while they are still available.

Tips on using a digital camera that will make mastering the contents of its user manual much less daunting

November 11, 2012. - You have to know how to use the manual controls of a digital camera in order to be able to unlock its full potential...

Click here! to read the article on this website.

The HDMI sound and vision transmission standard, its digital rights management system and other matters of interest

External video connectors

Video cards come equipped with a variety of combinations of external connectors to support a range of monitors and uses. A DB-15 (D-sub VGA) connector is used for standard output to an analog monitor. An S-video output connector is used to connect devices such as TVs and VCRs to the card. A DVI-D (DVI Digital) connector is typically used to connect digital flat-panel LCD monitors. Some graphics cards come with a DVI-I connector to accommodate analog monitors. The digital HDMI and DisplayPort standards are dealt with in the next item.

High Definition Multimedia Interface (HDMI)

If you want to use a video/graphics card with a HDMI (High Definition Multimedia Interface) output that combines sound and video, you have to cable the digital S/PDIF surround-sound output from the sound card or motherboard into the graphics card to provide HDMI with both sound and picture so as to take advantage of its full capabilities. However, note that if you are only using a 2.1 stereo speakers for the sound output, you will only get two-channel simulated surround sound from them. A 5.1 or 7.1 surround-sound speaker system is required for actual surround sound.

By July 2010, there was not yet an official standard for wireless HDMI, but some products have been made available that provide wireless 1080p video using an 802.11n wireless transmitter. An example of such a product is the Eminent iTrio EM7100 wireless home HDMI kit.

HDMI - high-definition multimedia interface -

HDMI Investigated - Are expensive cables a scam? -

Note that if you want to have HD audio over an HDMI connection, the motherboard chipset or the graphics card must support Protected Audio Path (PAP) that is used to enforce Digital Rights Management (DRM) protection on content. For example, your PC might have a motherboard that has an onboard graphics chip, such as the AMD 780G chipset that handles HDMI output, which was one of the first to support Blu-ray playback the is used for high-definition (HD) movies. However, that chipset does not support PAP, so you would have to install a graphics card in the PC that supports PAP, such as the Sapphire Radeon 5450 (price: around L40 in December 2010). It comes in two versions - half-height for installation in slimline cases and full-height - and is cooled by a passive heatsink, which doesn't have a fan. This will deliver HD audio to an external device, such as Onkyo 875 home cinema amplifier via an HDMI connection. To use a graphics card instead of onboard video, you should enter the PC's BIOS and disable any setting in it for onboard graphics. If there is no such setting there, disable the onboard display adapter (e.g., AMD 780G) under Display adapters in the Windows Device Manager. The graphics card will be identified by its make/model if its device drivers have been installed, so disable the second entry by right-clicking on it and selecting Disable.

Media streamers, also known as streaming multimedia receivers, use an HDMI connection to stream 1080p video to a TV from a desktop or laptop PC or network attached storage (NAS) device acting as a file server. For detailed information on media streamers on this website, visit the article called Media Steamers also known as Streaming Multimedia Receivers, which covers the specifications, the system requirements for media streaming, file format support and how to set up a UpnP server in Windows Media Player 12 (WMP 12) in Windows 7 and file sharing using an SMB server.

Rotating HDMI cables

Just as you can buy SATA drive cables that have the connector at a right angle to the cable for easier connections in restricted spaces, you can buy a rotating HDMI cable that can rotate to almost any angle. You can buy them from in 1m, 2m, 3m and 5m lengths - part codes: 41515, 41516, 41517 and 41518 respectively.

Wireless HDMI

Wireless HDMI kits are available that can be used instead of a long HDMI cable, but there are several competing standards - proprietary Wi-Fi that usually sends video in compressed form within a room, which can produce degraded quality when there is plenty of movement being displayed - UWB (Ultra Wideband) has a much shorter range than Wi-FI but a data transfer rate fast enough to provide uncompressed Full HD Blu-ray movies, however, usually requiring uninterrupted line of sight between the sending and receiving devices. Note that some HDMI kits provide an HDMI port on the transmitter and receiver, which means that that can be used with an HDMI cable and other devices. Other kits just use a USB dongle like most other wireless devices (network, printer, keyboard & mouse dongles, etc.), which require a computer as the transmitting device.

Can a signal produced from a HDMI cable really be transmitted wirelessly and maintain its quality? - Yes, with excellent results. The kit I use has these specifications: Wireless Full HD 1080p transmitter system, up to 1920x1080 screen-resolution support without loss of quality, up to 30m range in rooms and 15m from room to room and 1x HDMI input and 1x HDMI output port on the receiver and transmitter. Using it, I can stream SKY HD TV and Playstation 3 signals (additional kit is required for the two additional ports) from my lounge to my kitchen. The distance between the transmitter and the receiver is approximately 9/10m. The picture via this equipment displayed on the TV in the kitchen, a 42" Panasonic L42E30B, is excellent. The downside is that the kits currently (February 2012) cost around £150.


If you see the term HDMI/HDCP, the HDCP stands for High-bandwidth Digital Content Protection, which is the digital rights management system associated with HDMI. Protected Audio Path (PAP) protects audio content. -


Many LCD monitors now have extra video connections that allow them to be connected to a DVD player, games console or video camera, and some LCD monitors now provide an HDMI high-definition port and support HDCP that allows them to display the latest high-definition movies.

HDCP technology allows the monitors that support it to authenticate themselves to high-definition video sources, such as a high-definition movie, thereby proving that they are an approved method of displaying the video rather than an illicit device that could be used to copy it. The movie studios have the option of restricting full high-definition playback to HDCP devices only. (A PC's video/graphics card can also be an HDCP device.)

HDCP was developed by Intel. It encrypts the signal between the HD video source (the high-definition Blu-ray or HD DVD player/drive) and the display/monitor. Digital output from a Sky HD box, Blu-ray, or HD DVD player will not be dsiplayed if the DVI or HDMI input on the monitor isn't HDCP compatible. Windows Vista and Windows 7 also has HDCP support as part of its digital-rights-management (DRM) software.

When the movie studios start marketing HDCP-protected movies, if you want to watch them through a Windows Vista computer, the PC's monitor and the video/graphics card will have to support HDCP.

Connecting a DisplayPort port on a graphics card to DVI or HDMI port on a monitor

Question: A monitor with an analog or VGA or digital HDMI input port can be connected to the DVI-I port on a graphics card using inexpensive adapters, so why is that not the case with a digital DisplayPort output from a graphics card to an HDMI or DVI port on a monitor?

Answer: A DVI-D is a digital-only DVI port, so it can only be connected from a graphics card to a digital HDMI port on a monitor using an adapter cable, but a DVD-I port on a graphics card can carry both an analog VGA and a digital DVI signal so it can be connected to both types of port on a monitor. Don't buy an adapter that claims to be able to convert a digital DVI-D signal from a computer's graphics card to an analog VGA input port on a monitor, because that cannot be achieved.

The digital DisplayPort standard is not compatible with either the VGA or DVI standards, but you can buy adapter that can connect a DisplayPort output signal from a computer into a monitor's DVI-D, DVD-I or HDMI inputs. Just make sure that you buy an adapter the supports the correct DVI monitor input. Also note that there is also a second type of DisplayPort called Mini DisplayPort that uses a mini connector. An adapter for the standard type can't be used with a mini port. Passive DP++ DisplayPort ports can output HDMI and DVI signals, so a "Passive" DisplayPort-to-DVI or a DisplayPort-to-HDMI adapter costing around L10 is required. A standard DisplayPort output port requires an "Active" adapter costing around L25 that actively converts the video signal. Note that both passive and active adapters only support screen resolutions of up to but no higher than 1920x1200.

DisplayPort and Mini DisplayPort (from graphics card) to VGA (on monitor) adapters are also available from around L35.

How powerful must a PC be to play HD video?

June 14, 2007. - There are a large number of screen resolutions, video file formats, data transfer rates, and file-compression methods to be taken into consideration when attempting to answer the question how powerful a PC needs to be in order to play HD (high definition) video. Since h.264-encoded HD DVD and Blu-ray movies are the hardest to play back smoothly, it seems sensible to say which PC specification would be required to play it, because, if a PC can play it, it can play anything less demanding.

You should aim for a PC with at least either of these two dual-core processors: a 1.8GHz Intel Core 2 Duo or an 2.2GHz AMD Athlon 64 X2. (Most Intel and AMD dual-core processors provided in new desktop and laptop PCs available in May 2011 exceed those specifications.) The PC should also have a fairly recent PCI Express video/graphics card - an ATI Radeon X1000 series DirectX 9 card, or a nVidia GeForce 7000 or 8000 series DirectX 9 card. The graphics card should have at least 256MB of RAM memory, which all new cards have because most new cards have 512MB or more. Visit the following site for a list of current and obsolete graphics cards.

The Desktop Graphics Card Comparison Guide -

You should be using the most recent version of DVD software, such as Cyberlink PowerDVD, or InterVideo WinDVD.

How to save power

Read these two articles if you're interested in finding out how to go about saving power with regard to using computers. -

The Power Saving Guide -,review-2311.html

The Power Saving Guide, Part 2 -,review-2318.html

The image below of an AMD Radeon HD 6950 graphics card shows its two mini DisplayPorts (left), the analog VGA port (middle) and its two DVI-I ports that allow it to be connected to either a VGA or a DVI monitor using the correct cable.

AMD Radeon HD 6950 showing its two DisplayPorts, one analog VGA port and two DVI-I ports

The highest-end (in March 2011) and very expensive AMD Radeon HD 6990 graphics card shown below only has four DisplayPorts and a single DVI-I port, but DisplayPort-to-DVI adapters are supplied for the DisplayPorts.

AMD Radeon HD 6990 showing is four DisplayPorts and single DVI-I port

Note well that both of the graphics cards shown above (Radeon HD 6950 & 6990) use a single PCI Express x16 slot on the motherboard, but take up the space of two slots, so you have to make sure that the PC's motherboard has a PCI-E x16 slot and enough slots for your other adapter cards, because you won't be able to use the slot next to the slot that the graphics card is installed in.

Note that USB is not a graphics standard, but monitors that connect via a USB port are now available.

It is possible to buy a USB dock and an external USB graphics adapter to connect multiple monitors. Each USB graphics adapter is connected to the USB dock.

Using Multiple Monitors with The HP USB Dock & USB Graphics Adapters [Video] -

Common Multi Monitor Questions -

More detailed Information on the VGA and DVI graphics display standards is provided further on in this article.

Eyefinity technology by AMD/ATI supports up to six monitors that can show a different display. AMD recommends using DisplayPort monitors, which are currently not very common and tend to be expensive. Fortunately, Sapphire has released a DisplayPort-to-DVI adapter, making it possible to run three DVI monitors from any Eyefinity graphics card.

Standard single link DVI can only be used up to certain screen resolutions beyond which a dual link cable has to be used. The following link provides detailed information on single and dual link DVI.

Single-link and dual-link DVI : Wikipedia -

Maximum number of monitors Win 7 Supports? -

DisplayPort has been designed to replace analog VGA and digital DVI connectors in computer monitors and graphics cards and to replace internal digital LVDS links in computer monitor panels and TV panels.

DisplayPort -

In a desktop PC, a single graphic card is installed in an ISA, PCI, PCI-X (64-bit extended PCI), AGP, or PCI Express/PCI Express 2 (PCIe or PCI-E) slot on the computer's motherboard. The ISA standard is no longer used for graphics, but PCI and AGP graphics cards are still available.

Note that PCI Express 3.0 was released in November 2010, but the AMD Radeon 7970, launched on January 9, 2012, was the world's first PCI Express 3.0 graphics card. PCI Express 4.0 is expected to be finalised some time between 2014 and 2015. Reviews of the performance of PCIe 3.0 graphics cards makes it plain that the increase in performance from version 2.0 to version 3.0 is nowhere near the increase in performance between version 1.0 and version 2.0.

PCI Express -

The images at the top of this page show the kind of low-end video/graphics cards that are used in desktop PCs.

The image on the left above shows an ATI Radeon X1300 PCI Express video/graphics card with its built-in heatsink and fan unit. The image on the right shows a low-end ATI Radeon HD 2400 PCI Express video/graphics card with a passive cooling unit, which has no fan, just radiators. Low-end PCI and PCI Express graphics cards that are passively cooled are still widely available.

Most high-end graphics cards require onboard heatsink-and-fan cooling, while most low-end cards can make do with passive cooling - just a heatsink. However, it is now also possible to buy a high-end graphics card that uses passive cooling - just a heatsink, which makes the card silent. To use it as a gaming machine may just require adding additional internal cooling (one or more fans) to the PC's case. The following article explores a high-end PowerColor Radeon HD 6850 card with passive cooling:

A current low-end graphics card with passive cooling, or a motherboard with an integrated graphics chip (which is often not even passively cooled), is all that is required by an office desktop PC that runs office applications and accesses the web via a broadband connection.

It is possible to buy graphics-card coolers for high-end graphics cards (used for playing the latest PC games or doing high-intensity graphics work) that can be used instead of the cooler that came with a graphics card. For instance, if you want to overclock a particular high-end card's GPU (graphics processing unit) and require a more powerful cooler.

NVIDIA and AMD are the two major manufacturers of graphics chips. ATI was purchased by the processor-manufacturer, AMD, which has now dropped the the ATI name for its own name. So, instead of being called an ATI Radeon, the graphics cards are called AMD Radeon. AMD and NVIDIA make their own graphics cards and also sell the chips to other graphics-card manufacturers, such as Sapphire.

Any graphics card that you want to buy or that is part of a desktop or laptop PC will have reviews online. The search term graphics cards reviews will find them.

The chip(s) that power a graphics card are called a graphics processing unit (GPU). Currently, graphics cards with two GPUs are available. It is similar to having two processor cores in a dual-core processor. As with processor cores, which have now reached six cores (processing units) in a processor (hexa-core processors), more GPUs will no doubt be added to in future, just as installing more graphics cards on a single motherboard has become possible. At present, it is possible to use four graphics cards installed at once, using the PCI Express graphics standard.

Most desktop and laptop PCs have one video/graphics card, or a graphics chip integrated on the PC's motherboard or into the processor, which both Intel and AMD now provide on some of their processors, but it is possible to have four graphics cards installed on a desktop PC if the motherboard has four PCI Express x16 slots or even two PCI express x16 and two x8 PCI Express slots. Some graphics cards come with two graphics chips, so two such cards installed on the motherboard make four graphics chips. The MSI X58 Pro motherboard (Socket LGA 1366 for Intel Core i7 quad-core processors) has three PCI Express x16 slots for graphics card, so it is possible to run three compatible AMD/ATI Radeon graphics cards in a CrossFireX configuration on it.

In a laptop PC, the graphics chip is most commonly integrated into its motherboard or processor and uses system RAM memory, but, increasingly, high-end laptop PCs have separate video/graphics cards with their own graphics memory that can be removed and replaced or upgraded. If the graphics is integrated into the motherboard or processor, it cannot be upgraded (without upgrading the motherboard or processor to a superior graphics chip) unless there is an adapter slot inside the computer specifically for a graphics card upgrade, which most Lapps do not currently provide. However the laptop's motherboard can be replaced by its manufacturer (laptop motherboards cannot, at present, be purchased from computer shops).

All video/graphics cards have their own graphics RAM memory, which, on high-end cards has reached a massive 2GB. The PowerColor PCS HD4850 was the first graphics card with 2GB of memory, which is way over the top for most computer users.

As you can see, the benchmark results (article date: July 20, 2011) on the following page of a range of current graphics cards, the 2GB AMD Radeon 6950 card is outperformed by the 1GB model, but the 2GB card is more expensive. -

Search for how much graphics memory is required to locate articles on that topic. Add for a gaming PC if you need to know the ideal amount of graphics memory for a gaming PC. A graphics card with 1GB of memory can play the latest games and there is no need to spend a fortune. The AMD Radeon 6790 card costing around £116 (April 2011) plays the demanding Crysis at a very respectable 42fps at a screen resolution of 1,680x1,050 with High detail and 4x anti-aliasing enabled.

Graphics memory currently in use is of three main types - GDDR3, GDDR4 and GDDR5. GDDR5 is the latest version of DDR graphics memory, which, as is the case with memory, only provides a slight performance edge over its predecessors.

Note well that you must fit an expansion card in its correct type of motherboard slot. Installing an expansion card in the wrong type of slot could make the expansion card or even the computer itself unusable unless the card or the motherboard is replaced. Always follow the golden rule with electronic components - Never force them to fit because they are designed to fit easily.

PC motherboards that incorporate features that are usually added by adapter cards fitted into their PCI, PCI-X/AGP/PCI Express slots, such as video, sound, and network cards, are becoming more desirable, because, as technology advances, integrated electronics can compete ever-more effectively with adapter cards.

Note that some motherboards have a PCI-X slot. PCI-X is the extended PCI standard, both of which have been replaced by the PCI Express standard. The 64-bit PCI-X bus slot has double the maximum throughput of PCI, at a maximum speed of 3Gbps. Most PCI-X cards are backwards compatible with PCI bus slots, which means that you can install a PCI-X card in a PCI slot provided that it has the correct voltage keying for the slot and that the area directly behind a PCI slot must have available space to accommodate the additional length of PCI-X cards.

However, if you want to play the latest PC games or use graphic-intensive applications, such as video-editing and computer-aided design (CAD) applications, you would always choose a desktop PC or laptop PC that has its own dedicated video/graphics card instead of integrated graphics. This is because integrated graphics on the motherboard or processor are still currently inadequate for such tasks. Using the search term integrated graphics provides links to many articles on that subject.

The image below shows the slot arrangement on a typical motherboard with an AGP graphics port.

The slot arrangement on a motherboard

A recent motherboard would have either an AGP slot or a PCI Express x16 slot. The AGP graphics standard is no longer used on most new motherboards, having been replaced by the PCI Express, PCI Express 2.0 and 3.0 standards. Some motherboards can have four PCI Express slots for graphics cards (x16 and x8 slots). The MSI X48 Platinum motherboard has four PCI Express x16 slots that can accommodate four graphics cards. PCI Express x1 slots are used for devices, such as some graphics cards, sound cards, and Ethernet network cards.

The following diagram shows the PCI Express x16 and x1 slots, and the two standard PCI slots on a Gigabyte GA-MA78GM-S2H motherboard.

The PCI Express x16 and x1 slots and  the standard PCI slots on a  Gigabyte GA-MA78GM-S2H motherboard

he AGP graphics standard is outgoing technology that is no longer found in new PCs. However, at the time of reviewing this page (April, 2011), it was possible to buy an AGP graphics card that supports DirectX 10, which initially only worked with Windows Vista. DirectX 11.0 was the latest version in April 2011. It only runs on Windows Vista and Windows 7.

The PCI graphics standard that uses standard PCI slots, preceded the AGP standard, yet it is still possible to buy a PCI graphics card that supports DirectX 9.0, which is supported by Windows 7, the latest versions of Windows. Therefore, if you have a fairly recent PC, such as the Dell Dimension 3000 from 2006, which has onboard graphics (a graphics chip on the motherboard and three PCI Express slots (no AGP or PCI Express slots), you can use Windows 7 if you obtain a PCI Express card that supports DirectX 9.0, such as the ZOTAC 256MB GEF FX5200.

Note that you can now also obtain DirectX 10 for Windows XP, which wasn't the case until recently; DirectX 10 could only be used with Windows Vista. Download pages can be found by using a search term such as windows xp directx 10.

An example of an affordable AGP card that supports DirectX 10 that can play the latest PC games is the Sapphire HD3850 graphics card that has 512MB of GDDR3 memory.

PCI Express 1.x/PCI Express 2.0 are the current graphics standards. PCI Express 2.0 motherboard slots are backwards-compatible with PCI Express 1.x. PCI Express 2.0 graphics cards are compatible with PCI Express 1.1 motherboards, which means that they will run on them using the available bandwidth of PCI Express 1.1. Therefore, you should also be able to run a PCI Express 1.x graphics card on a PCI Express 2.0 motherboard.

Some motherboards have two PCI Express x16 slots for two graphics cards. Some motherboards have four PCI Express x16 slots for four graphics cards. Other motherboards have two x16 and two x8 slots. The x8 slots can accommodate graphics cards as well, making a total of four graphics cards.

The image below is of the MSI K9A2 Platinum (AMD Socket AM2+) motherboard, which has four PCI Express x16 slots for four graphics cards. They are the four long vertical light and darker blue slots. When the appropriate slot cover is removed from the back of the PC's case, a graphics card is inserted in the selected slot and screwed to the case so that its ports panel containing its connectors appears at the back of the case. The two shorter white slots are standard PCI-X slots.

MSI K9A2 Platinum Socket AM2+66 motherboard with 4 PCI Express x16 slots for 4 graphics cards using ATI CrossFire technology

This motherboard supports the PCI Express 2.0 standard, which is fully backwards compatible with PCI Express 1.0 graphics cards (a PCI Express 1.0 graphics card can be installed in a PCI Express 2.0 slot). It supports QuadFire (four-way CrossFire) and SAS (serial attached SCSI hard disk drives).

The graphics-rendering power required by a computer that is delivered by one or more video/graphics cards depends on how graphics-intensive the software it runs is. For the best rendition (display) of graphics, the latest PC games require as much graphics processing power as can be provided. The graphics cards used by professional graphics software developers and computer-aided designers can be purchased costing many thousands of pounds, but a high-end graphics card used in a PC typically costs between L250 and L400. PC games such as Doom 3 and Call of Duty 4 can be played with a graphics card costing around L100 or less, but only by lowering the screen resolution and the amount of graphical detail that is displayed.

The order of the evolution of video/graphics cards is ISA => PCI => AGP => PCI Express. The ISA standard is no longer used for graphics cards. PCI and AGP video cards are still available, but those standards are being replaced by the latest PCI Express standard.

Note that PCI Express 3.0 was released in November 2010, but the the AMD Radeon 7970, launched on January 9, 2012, was the world's first PCI Express 3.0 graphics card. PCI Express 4.0 is expected to be finalised some time between 2014 and 2015. Reviews of the performance of PCIe 3.0 graphics cards makes it plain that the increase in performance from version 2.0 to version 3.0 is nowhere near the increase in performance between version 1.0 and version 2.0.

PCI Express -

As with previous upgrades to the initial specification, PCI Express 3.0 is backwards-compatible with earlier versions of the standard.

The following webpage provides access to full lists of all of the graphics cards (with technical specifications) made by the major card manufacturers. NVIDIA and AMD (which used to be called ATI and still is in the lists provided) are now the two largest manufacturers.

The Desktop Graphics Card Comparison Guide -

If you see a description of or come across a graphics card that has a X2 in its model name, it means that the card has two graphics processing units (GPUs), in effect making it two graphics cards in one.

Since most graphics cards use graphics chips made by NVIDIA or AMD, Wikipedia lists their specifications and the versions of DirectX and OpenGL that they support on these two pages:

Comparison of AMD Graphics Processing Units -

Comparison of NVIDIA Graphics Processing Units -

Best Graphics Cards For The Money -

Choosing a PC's power supply unit (PSU)

Choosing a power supply for your self-built desktop PC or an upgrade power supply that can run a new power-hungry graphics card is an important factor that can easily be underdone or overdone, depending on your computing needs. Overdone is better than underdone, because overdone just increases the cost of the unit, while underdone can render the computer unusable. A PC-gaming computer requires much more power than an office computer. The following power calculator allows you to enter the components. When all of the components are entered, the calculator tells you the wattage you require, which allows you to choose a power supply that provides that wattage plus some overhead just in case all of the components are being used at the same time.

Enermax Power Supply Calculator -

Note that the power-supply calculator takes the power used by the motherboard itself into consideration.

Windows 7 can only start up in Safe Mode if the computer it is being installed on doesn't have a graphics card that supports DirectX 9.0 or higher

Note well that Windows 7 requires a graphics/video card/chip that supports DirectX 9.0. For example, a Dell Dimension 3000 has an Integrated Intel Extreme Graphics 2 built into the PC's motherboard, which only has three PCI slots (no slots for an AGP or PCI Express graphics card.) The integrated graphics only supports DirectX 8.0, so when Windows 7 is installed it will only be able to start up in Safe Mode.

To find out which version of DirectX your computer is using, enter dxdiag in the Start => Run box (Windows XP) and the Start => Start Search box (Windows Vista). DirectX 9.0 is the highest Microsoft version that Windows XP can run. Third-party versions of DirectX 10 are available for Windows XP. Only Windows Vista and Windows 7 can run DirectX 10.0 and DirectX 11.0.

This is what the Windows 7 compatibility report says about the graphics on a Dell Dimension 3000:

"Windows Aero Not capable Your current graphics adapter won't support the Windows Aero user interface. Contact your PC manufacturer or retailer to see if an upgrade is possible."

Dell used a cheapo DirectX 8.0 chip in this 2006 computer. That shows the weakness in the compatibility report. It should have said that the graphics chip only supports DirectX 8.0 and that Windows 7 cannot be used unless the graphics card can be upgraded to a DirectX 9.0 card.

Fortunately, PCI graphics cards, one of the oldest standards, that support DirectX 9.0 are still available. For example, the ZOTAC 256MB GEF FX5200 PCI card was still available in May 2011.

The confusing myriad of cables that computers use

The myriad of cables that are in use are often very confusing to the home computer user. The following link provides a slide show of the cables and information on what each cable is used for that should dispel most of the confusion.

Here is another similar page that goes through every possible type of connector:

The most important consideration with regard to a video card of any standard is that it must be supported by the motherboard on which it is to be installed. The motherboard must have the correct slot for a particular video/graphics card.

The next most important consideration is that the PC's power supply must be up to powering a particular video card, or dual-card setup. Many video/graphics cards require an additional six-pin power connector to be connected to them from the power supply. Dual-card setups can easily require at least a 600W power supply that has a pair of auxiliary six-pin connectors. You can check (AMD CrossFire) and (nVidia SLI) for certified components.

High-end AMD and nVidia graphics cards, especially dual-card setups, require plenty of power. Power consumption at or over 200 Watts are not unusual. In dual-card configurations built around SLI or Crossfire technologies, the graphics processing can add 500 watts or more to a systems total power consumption. Not many standard, non-gaming PC's have a power supply unit (PSU) that is up to those kind of power demands, therefore always take the power supply into careful consideration if you plan to convert a standard PC into a gaming machine.

The performance boost that is provided by SLI or Crossfire setups varies from one game to the next. Support for these technologies has not been perfected, which still makes it possible to obtain better performance from a single high-end graphics card setup.

PSUs: More Important than You Think [August 2007] -,review-2385.html

In August 2008, the ATI Radeon HD 4870 X2 and the nVidia GeForce GTX 280 were the fastest graphics cards from AMD/ATI and nVidia respectively. Both cards are 270mm long, which is unusually long, so they may not fit in a PC's case. They also require one 8-pin and one 6-pin power connector from the power supply unit. If a PC's power supply cannot provide both connectors, a power-supply upgrade is required. Therefore, you should research the size and power requirements before you buy a new graphics card.

Although they have their own heatsink and fan units, very large and long graphics cards, for example, those based on the Radeon HD 4870 X2 chips and the nVidia GeForce GTX 280 chip, can get very hot if the cooling in the case is inadequate, so you should have case fans installed in the front and the rear of the case - the front fan sucking air in and the back fan expelling it.

A power-hungry video/graphics card, which will generate a lot of heat, can make a PC crash even if it has an adequate power supply. The cooling inside the case could be inadequate, causing the PC to overheat and crash. Adding more or replacing existing cooling fans in the case can rectify such a problem. The case might have additional fan-mounting points at the front or rear of the case. Some fans can be attached to the PC's motherboard, so, if you don't know where their connection points are located, consult the user manual for that make/model of board. If you don't have a copy, you should be able to download one in the PDF format from its manufacturer's website. If the existing case does not have any spare fan-mounting points, you may have to buy another case that provides adequate cooling options.

Another recent change in graphics technology is the introduction of DirectX 10 and DirectX 11.0. DirectX is the software standard that allows games developers to create games that will work on all of the PCs in the world. DirectX 9 was released in 2002, and most of the current games use it. DirectX 10 was released at the same time as Windows Vista (January, 2007). DirectX 11.0 was released with Windows 7 October 27, 2009. It adds some very impressive new effects that make games more realistic. DirectX 10.0 initially required a PC running Windows Vista, a DirectX 10 video/graphics card, and PC games that support DirectX 10. Both version 10 and 11 run on Windows Vista and Windows 7, but not on Windows XP.

Note that you can now also obtain DirectX 10 for Windows XP, which wasn't the case at first; DirectX 10 could only be used with Windows Vista. Download pages can be found by using a search term such as windows xp directx 10.

A PC game that uses the latest version of DirectX almost always provides a version of the game for the earlier version of DirectX.


The first ISA video/graphics cards had very little onboard graphics RAM memory, which was measured in kilobytes (KB) instead of megabytes (MB). Ten years ago, 1MB and 2MB video cards were high-end cards. After the standard progressed to the PCI bus, quickly followed by the AGP bus and then the PCI Express bus, the amount of RAM quickly increased to 4MB, 8MB, 16MB, 32MB, 64MB, 128MB, 256MB, and 512MB, 1024MB and 2048BB (1GB/2GB) where most AGP and PCI Express high-end cards are at present.

The amount of graphics RAM memory that a video/graphics card has is usually of the utmost importance in determining its performance, because a graphics card uses its memory to store the information of the textures that games display. When the card's memory is used up, it has to make use of the PC's system RAM memory, which is slower than obtaining the textures directly from the graphics card's memory.


How to install a video/graphics card in a PC's motherboard

Visit Page 2 of this article for information on how to install a graphics card (or dual cards) in a PC's motherboard. Information is also provided on how to identify the graphics card that is already installed. Use your browser'sBack button to return to this point on this page.

A quick way of identifying a computer's graphics card is to make use of the free GPU-Z utility.

512MB video/graphics cards

In May 2005, the first 512MB PCI Express graphics cards became available.

Recently, both NVIDIA and AMD/ATI have developed technology that makes it possible to install two or more graphics cards on a computer's motherboard. As many graphics cards can be installed as the PC's motherboard has slots for them.

1GB video/graphics cards

At the end of March 2006, ATI (now called AMD) released the first graphics cards with 1GB (1024MB) of memory. For more information and news on these cards, use a search term such as 1GB graphics cards.

Motherboards that can run dual video/graphics cards

PC motherboards that can run two or more PCI Express video cards with graphics chips made by NVIDIA are available that run in SLI mode. ATI's response is dual-card technology called CrossFire. Some motherboards have become available that can run four graphic cards - as two sets of dual cards in both SLI and CrossFire modes. If you want to use one of these modes, you should check that your PC's motherboard supports it.

The following FAQ page answers many questions regarding these graphics technologies, including the question: Can you use SLI on a CrossFire board or can you use CrossFire on a SLI board? -

Quad SLI: Motherboards that can run four video/graphics chips

Believe it or not, it has also become possible to buy a motherboard that can run four graphics chips linked in SLI mode.

Quad SLI uses two PCI Express x16 slots on such a motherboard that run two special nVidia GeForce 7950 GX2 graphics cards. Each of the cards has two circuits that have their own graphics chip, memory, and cooling system that are connected by an internal SLI link.

If two of the special graphics cards are installed, several new modes of operation are available, including one in which each of the chips produces an alternative frame.

ATI's quad-chip QuadFire graphics system and a review of a motherboard capable of running it

QuadFire: CrossFire-on-a-Stick -,review-2135.html

Review: MSI K9A2 Platinum motherboard -,1765-7.html

Always remember that today's exceptional system costing an arm and a leg is tommorrow's standard system that is easily affordable.

Don't confuse PCI-X (or PCIx) with the PCI Express standard, because it stands for PCI Extended, which is a much improved extension of the PCI standard that is fully backwardly compatible with the previous versions of the PCI 2.x standard.

ISA (Industry Standard Architecture) technology is now redundant. PCI (Peripheral Component Interconnect) video cards are still available new, but this will soon be redundant technology. Many computers in use still use AGP (Accelerated Graphics Port) technology, because it has been in existence for so long, but the AGP video/graphics standard has been superseded by PCI Express technology, currently up to version 3.0 (May, 2011).

The GPU (graphics processing unit) of video cards, and the processing chip on sound cards, have taken over most of the tasks of rendering graphics and sound reproduction from the processor (CPU), thereby allowing it to concentrate on running the rest of the system more efficiently.

A graphics chip can be an integral part of the motherboard, in which case, the motherboard will have one or more inbuilt video ports to which a monitor's cable is connected. More information is provided about these ports a little further down this page. If there is an AGP or PCI Express slot on a motherboard that also has an inbuilt AGP or PCI Express video chip, that chip can usually be disabled in the BIOS or by setting a jumper on the motherboard so that the AGP or PCI Express slot can be fitted with an AGP or PCI Express video card. If there is neither an entry in the BIOS or a jumper on the motherboard that disables the onboard video chip, then the process is automatic. You install the video card in its slot, attach the monitor to it, and it automatically becomes the primary video card.

An example of a motherboard with a built-in PCI Express chip (ATI RADEON XPRESS 200) is the MSI RS480M2-IL. Click here! to see annotated images of it on this website. It's analog VGA port is connected to the integrated ATI graphics chip. Motherboards can also provide digital integrated DVI graphics.

Almost everything is configured automatically by the very limited BIOS, including the processor's speed, the RAM, and the graphics card.

Note that any new, relatively cheap PCI or AGP or PCI Express graphics card will provide first-class 2D graphics of the kind that is used for office applications (word-processors, databases, etc.), and for digital photo editing, web design and accounts, but a relatively expensive 3D graphics card with 1GB or more of graphics memory typically only provides 2% to 3% better performance in 2D mode than a cheap L30 graphics card with only 256MB of memory.

Video display standards

Analog D-sub VGA and digital DVI interfaces on video/graphics cards and monitors

The two main graphics display standards currently being used in desktop and laptop PCs are VGA (outgoing, analog) and DVI (current, digital). The DisplayPort video display standard is being promoted as the successor to the DVI graphics standard, but, at the time of writing (May 2011), it was present but had not come anywhere near to achieving that goal.

Most new video/graphics cards can provide the following ports (connectors) - an analog D-sub VGA port for an analog CRT monitor and a DVI (DigitalVisual Interface) output port that connects to a DVI port on an LCD monitor. Some graphics cards don't provide a VGA port, in which case it is usually replaced by a second DVI port. DisplayPort ports are becoming more common. Some graphics cards provide all three types of output ports.

The image below of an AMD Radeon HD 6950 graphics card shows its two mini DisplayPorts (left), the analog VGA port (middle) and its two DVI-I ports that allow it to be connected to either a VGA or a DVI monitor using the correct cable.

AMD Radeon HD 6950 showing its two DisplayPorts, one analog VGA port and two DVI-I ports

The images below show the blue VGA port and DVI-I port more clearly.

Some graphics cards used to provide a VIVO (Video In Video Out) port that allows video to be captured for editing and then returned to an analog device such as a VHS recorder, but, due to a lack of demand created by the dominance of digital DVI, which makes it redundant, this port has been dropped. If you need to know about VIVO, visit the following webpage.


Both DVI-to-VGA and VGA-to-DVI converters are available. The cost depends on which type of DVI port is being connected to a VGA port and whether the port is on the monitor or coming from the computer. The port on the computer is named first in the converter's name. So a DVI-D-to-VGA converter converts a DVI-D signal from the computer to a VGA input on the monitor. A DVI-D-to-VGA converter that connects computers with a DVI-D connector to analog VGA monitors or projectors is particularly expensive. In most cases, it would be cheaper to buy a new monitor or graphics card with the required connectors than to buy such a converter.

You can conduct a web search for these converters.

Note that some LCD monitors have both an analog D-sub VGA port and a DVI port, but some only have a VGA or a DVI port. The two types of port are completely different electronically and in size, and so a different cable is used to connect the video card to the monitor.

With digital DVI and the introduction of digital HDMI that carries the video and sound, most new video cards no longer provide an analog S-video out port that connects a television set (but which cannot carry sound) to the computer as an additional display. An S-Video connection doesn't have sufficient bandwidth to make it suitable to transmit high-definition video signals.

If it is a boxed, retail product, the video card should come with all of the cables it has ports for, but an OEM card, supported by the vendor only, not the manufacturer, is usually sold without any cables. If the TV set has only a composite (a yellow phono-type input port) or a SCART port and the video card has an S-video output port, the S-video signal from the video card can be converted by using a cheap adapter.

There is more information on this subject, plus images, further down this page.

Most video/graphics cards that have both DVI and VGA output ports can run monitors from both of them at the same time.

ATI Radeon 9700 Pro video card Close up of the DVI and D-sub ports on a video/graphics card

The top image above shows an ATI Radeon graphics card that has a standard analog D-sub VGA port (left, small, blue), which is older technology, and a purely digital DVI-D port, which is the current digital technology. The image below it shows a close-up view of the ports panel of another graphics card. It has a standard (blue) analog D-sub VGA port and a DVI-I port, currently the most common type, which can produce both analog VGA and digital DVI signals. A DVI-I port has four pin holes next to the the main body pin holes (three rows of eight) that carry the VGA signal. If you have a PC monitor that only has an analog VGA connector, you can connect the graphics card (with a DVI-I connector) and the monitor by using a cheap DVI-to-VGA cable that is often provided with a graphics card. The cable simply connects the four pins carrying the VGA signal to a DVI-I connector on the monitor.

If you are unsure whether or not a particular DVI or VGA connection is possible, you can conduct a web search, such as this one: dvi-i on video card dvi-d on monitor, which produced the following link.

The following link to a computer forum discusses how to connect a monitor with a DVI-D port and a graphics card that has a DVI-I port.

DVI-D Monitor....DVI-I Computer: Will it work? -

A DVI-D port on a graphics card (or integrated motherboard) is purely digital. If you want to connect one to a VGA monitor, you would have to use a digital-to-analog converter/adapter, which is an actual device that costs around L200 or more. You would have to choose between buying a new digital monitor or an expensive adapter.

Below are the magnified images of a standard analog D-sub VGA connector of a VGA port (left) and a DVI-D port (right). As you can see, the four pin holes required to carry a VGA signal are not present.

Close-up view of a VGA D-sub port on a video card or built into a motherboard with an integrated video chip Close-up of a DVI -D port on a video card or on a motherboard which has an integrated video chip

Many current high-end graphics cards have two DVI ports (no D-sub VGA port), which could be two DVI-D ports, or one DVI-D port and one DVI-I port. You can connect the card to two monitors that can then display different applications.

If the motherboard chipset supports the DVI/HDCP and the high-definition HDMI graphics standards, it is possible to use a DVI-to-HDMI adapter cable to convert a DVI signal to a high-definition HDMI input signal of a high-definition TV or monitor. Here is an extract from the manual of the Asrock K10N78FullHD-hSLI (AMD Socket AM2+) motherboard.

An extract from the manual of the Asrock K10N78FullHD-hSLI (AMD Socket AM2+) motherboard.

Video display standards: The new DisplayPort graphics interface

The DisplayPort graphics standard is being promoted as the successor to the DVI video display standard. The bandwidth of the dual-link DVI standard (that uses a special dual-link cable) can barely handle screen resolutions of 2560x1600 pixels for large widescreen displays; using higher resolutions requires a reduction of the refresh rate. The HDMI standard has similar limitations, but this is not a problem yet because HD TVs are unlikely to go beyond using a resolution of 1920x1080 pixels for several years to come. The current DisplayPort 1.1 standard has similar limitations to dual-link DVI, but greater bandwidth is expected, going up to resolutions of 3840x2400 pixels. DisplayPort graphics cards drive LCD screens directly, so don't have to make use of the current electronics, which should make the displays slimmer and cheaper. It remains to be seen if the standard succeeds in replacing the DVI and HDMI graphics standards.

DisplayPort - FAQ -

How to use two monitors with the same video card or two video cards

Read the Q&A on this site called Can I use the DVI and the VGA ports on my video card to run two monitors? to find out if doing that is possible with a particular video card. Use your browser's Back button to backtrack.

How to use multiple monitors in Windows Vista and Windows 7

Using multiple monitors in Windows XP is a plug-and play operation. You can install two or three video cards in the computer's PCI Express slots and then plug in three monitors, and XP recognises them almost every time. However, doing that in the Windows Vista Home Premium or Vista Ultimate versions, which support the Aero Glass feature, is not so easy. Here is the information on Microsoft's site on how to do so:

In Windows 7, you just have to connect the two monitors and it sets them up. If you move the mouse pointer to the edge of the screen, it moves on to the next screen, etc. You can run an application or web browser on each monitor.

Unfortunately, Windows won't stretch the taskbar on a dual-monitor system to the second monitor. However, free software is available that creates a second taskbar on the secondary monitor. The free Dual Monitor Taskbar can be downloaded from It has only been tested on Windows 7 and Windows 2008 Server R2, but might work on Windows XP and Windows Vista.

Click here! to go more information on this topic on this website.

Overclocking a video/graphics card

How To Overclock Your Graphics Card -,review-30739.html

BIOS Flash - Overclock Your Graphics Card in 5 Minutes -

The image below shows an example of a graphics card with two DVI ports, which could be a DVI-D port and a DVI-I port, two DVI-D ports, or two DVI-I ports.

An nVidia GeForce 7900 GT graphics card

If you require more information about the VGA and DVI graphics interfaces (DVI is the most complicated graphics interface), visit the following pages:

All About DVI - A Complete Guide to the Digital Video Interface -

VGA (Video Graphics Array) -

DVI (Digital Visual Interface) -

The dual-link DVI interface and cable

Some LCD PC monitors, such as the 30" Hazro HZ30WS, has a native screen resolution of 2,560x1,600 that exceeds the capabilities of single-link DVI, which can manage screen resolutions up to 1,920x1,200. Most graphics cards can manage higher resolutions, such as 2,560x1,600, but a dual-link DVI cable has to be used instead of the single-link version.

A dual-link cable has a full complement of 24 pins in a 3x8 configuration. A single-link cable has two 9-pin blocks that omits the six pins in the centre of the connector.


Apart from the drivers for notebook/laptop computers, driver development is now being exclusively handled by the manufacturer's of the graphics chips (AMD/ATI, NVIDIA, etc.) used in graphics cards, not by the manufacturers of the entire video/graphics cards (Sapphire, ZOTAC, etc.), but the drivers are also made available from the third-party manufacturers' websites. For example, Sapphire provides "new and archived drivers for graphics cards, sound, network, BIOS, and chipset components" from its website.

Regular visits to a particular graphics-card manufacturer's website is a good idea, because you could still download updates for utilities and tools, or download a newer version of the BIOS for the card.

The end of this section of this page deals with the video-card BIOS.

The drivers on the CD that comes with a new graphics card (or new computer) will probably already be out of date by the time you buy it. Therefore, it's a good idea to download the latest drivers from the card-manufacturer's or the graphics chipset manufacturer's website. Newer games tend to have problems with older drivers. The same is true for Microsoft's DirectX, which you should also keep up to date. Newer games often ship with the runtime installer of the current version of DirectX, which you run while online to install the latest version.


The following quotation comes from the ATI website (taken some time ago):

"You MUST use the drivers supplied with your laptop or notebook computer, or obtain a driver update from the manufacturer of your laptop or notebook computer."

That rule is no longer necessarily the case.

In other words, because the video chips used in laptop/notebook computers have an architecture that is customised to to a particular laptop/notebook computer manufacturer's monitor requirements, etc., as opposed to the standard architecture of the chips used in PCI, AGP and PCI Express video/graphics cards and graphics chips integrated into motherboards, AMD (used to be called ATI) and NVIDIA do not update the drivers. To do so would be uneconomic for them (the two major graphics-chip manufacturers), therefore the computer manufacturer is the only source of updated drivers.

Obviously, if the laptop/notebook manufacturer does not update the drivers, then there is no other source for them. - This is clearly yet another factor to be borne in mind when purchasing a laptop/notebook computer, because updated drivers are often required in order to be able to install new versions of Windows, such as Windows 7, and updated versions of DirectX and OpenGL that are in turn required in order to run the latest games.

Using the Mobility Modder tool to adapt the standard ATI and Nvidia laptop graphics device drivers

With the Mobility Modder tool, you can use the standard ATI or NVIDIA drivers on your laptop. Instructions on using the tool for ATI mobile graphics chipsets can be found at:

Note the final version supports up to the ATI MOBILITY Radeon HD 4870 X2 chipset.

For NVIDIA laptop graphics chipsets the page is:

The current supported chipsets are provided on that page.

Omega drivers

If you buy a non-brand-name laptop/notebook computer, advertised as a gaming machine, from a manufacturer that has the computers made cheaply in the Far East, which won't be creating updated drivers, you might not be able to play games that require updated drivers.

Many laptop/notebook computers use AMD/ATI and NVIDIA graphics chips. If this is the case and updated drivers are not available from the manufacturer, you might be able to use the Omega drivers that are created by Angel Trinidad in his spare time. The drivers are based on the official ATI and NVIDIA drivers, and are modified for gaming performance.

They can be obtained from:

Read this Q&A on this website for more information on the problem:

I can't update the device drivers for my Tiny notebook/laptop computer.

If the sources of drivers provided above prove to be of no use, there may be other sources of driver updates for the latest graphics chipsets provided on the web that you can find by using a suitable search term containing the chipset's name and the word driver.


Note that installing the latest drivers for a device can sometimes cause problems, or even render the device or even the whole system unusable until a fix of some kind is applied.

If this is the case, in a Windows 9.x/Windows XP/Vista/Windows 7 system, uninstall the device in Safe Mode by pressing the F8 key at start-up to bring up the boot menu, and then choose Safe Mode from the list. Open the Device Manager and remove the device, then allow Windows to reinstall the drivers, and, if necessary, install an earlier version.

Windows XP/Vista/Windows 7 have a Roll Back Driver feature in the Device Manager that allows you to roll the system back to the state it was in before you installed a new driver file. You can also use its System Restore feature to roll the whole system back to a former state (all of the system files are changed back to the versions that were in use on the date when a particular restore point was created).

Visit the Recovering Windows XP page on this site for more information on both of those features.

DirectX and OpenGL

DirectX is a kind of super software device driver. It is Microsoft's graphics software that is used by games developers in the creation of their games. The set of controls that are used to create the 3D effects in most modern games are defined by DirectX.

A standard software device driver usually just makes it possible for the programs or applications that use a hardware device, such as a video or sound card, to be able to do so. DirectX does that, but if the hardware is found to be lacking it can also emulate the missing hardware capabilities in its software. This feature is known as the program's Hardware Abstraction Layer (HAL).

To make 3D video acceleration possible, developers of 3D software need a standard language in which the 3D output is programmed. Such a standard, or API (Advanced Programming Interface) determines which operations a graphics chip must support.

Currently, the dominant 3D standards are OpenGL and Microsoft's Direct3D, which is a component of DirectX. Most PC games are designed to use Direct3D, so when Microsoft releases a new version of DirectX, most of the new functions are soon incorporated into OpenGL.

DirectX and OpenGL are the 3D programming interfaces used by graphics cards to play most graphics-intensive games.

DirectX 10.0 and 11.0

Windows XP can only officially use DirectX 9.0c. However, if you search for xp directx 10 you can find third-party versions that work with Windows XP.

DirectX 10 is not backward compatible with previous versions, as is the case with the previous versions, which are backward compatible with previous versions. However, Directx 9 is emulated in DirectX 10, which means that it can run DirectX 9 games.

Direct X 11.0 arrived with Windows 7 on 22 October 2009. It is available for Windows Vista but not for Windows XP.

Visit this Q&A - Should I buy a DirectX 10 or a DirectX 11 video/graphics card?.

In order to play DirectX 10 games, a PC must have a graphics card that supports its technology, such as the NVIDIA GeForce 8800GTX card. For that matter, the graphics card must support a particular version of DirectX in order to be able to use it.

However, because of the large number of PC that have graphics cards that don't support DirectX 10, games designed to use it will come with a version of DirectX 9.0c that does play them.

DirectX 11 is part of Windows 7. It is available for Windows Vista users, but not to Windows XP users.

List of games with DirectX 11 support -

Note that Microsoft no longer provides a seoarate page on DirectX that provides versions for downloading. DirectX is updated by Windows Update automatically along with other security updates and hotfixes.

The video-card's BIOS setup program

All video cards - using ISA, PCI, AGP, and PCI Express motherboard slots - have a BIOS setup program that accesses a BIOS chip on the card in the same way as the system's BIOS setup program accesses the BIOS chip built into a computer's motherboard. Updates for the BIOS file can be made available for both the motherboard's system BIOS and the video card's BIOS from the motherboard manufacturer's and the video card manufacturer's sites respectively. Instructions on how to update the BIOS are usually also supplied. Often new features can be added by updating a video card's BIOS, because the manufacturer often uses the same video chip on high-end and low-end cards, and it's the BIOS that limits the low-end card. If that is the case, doing nothing more than updating the BIOS can make a low-end card function like its high-end relative. Updating a video card's BIOS can also sometimes solve problems that are otherwise insolvable.

But note that you cannot access the settings of the BIOS of a video card as you can access the settings of the motherboard's system BIOS by pressing the entry key(s) at start-up to run the BIOS setup program.

Advanced Guide: Flashing a Video Card BIOS -

You should be able to find other guides on this subject by using a web search query, such as: flashing video card bios.

Computer hardware troubleshooting flowcharts

As you can see from looking at any of the diagnostic charts made available from the following link, there are no photo-illustrations or explanations of basic computer functions. The intended audience is the hobbyist or technician who already has some experience of repairing computers.

If you can understand a particular flowchart, it would be a good idea to print them just in case you can't boot your computer and you need the information.

Video Card Diagnostics -

There are other flowcharts covering the motherboard, disk drives, etc. and laptop repairs.

The power requirements of the power supply unit (PSU)

The maximum amperage delivered by the +12V rail of a power supply unit (PSU) is of particular importance with modern high-performance systems. The PSU unit itself always has the power details of its different rails printed on it.

Most motherboard manuals tell you what the amperage of the +12V rail has to be in order to power the motherboard properly.

For example, the manual for the MSI RS480M2-IL motherboard, which has an inbuilt video chip and therefore doesn't require a video card to be installed, says that the +12V rail must supply at least 18A (amps) of current. Many cheap off-the shelf PSUs provide only 15A or less of current on the +12V rail, and therefore can't be used with that motherboard if you want a stable system.

If you want to install a high-end video/graphics card the +12V rail would have to deliver between 20A and 30A. Therefore, you should always make sure that the PSU in a system can match the power requirements of a high-end video card before you buy or install it.

For example, it was the middle of June, 2005, and NVIDIA had just released its long-awaited 7800 GTX graphics chip. A single video/graphics card using the chip requires the minimum of a 400W PSU with a +12V rating of 26A, while the SLI, dual-card configuration, requires a 500W PSU with a +12V rating of 34A as the minimum. Most standard PSUs did not usually deliver either 26A or 34A on the +12V rail, so a special PSU was required to run both of those options.

The PCI Express standard as the latest standard for graphics cards

A new standard of PCI bus called PCI Express (abbreviated to PCIe and PCI-E) has replaced the PCI and AGP graphics interfaces for adapter cards. Since it can be bridged to the PCI bus, it can be used to run the the same kind of adapter cards that are presently run on the standard PCI bus - and can also run the fastest PCI Express video cards.

In May 2008, the PCI Express 2.0 standard was in the process of replacing its forerunner. It provides double the bandwidth for data transfers that the original standard delivers.

Note that PCI Express 3.0 was released in November 2010, but the the AMD Radeon 7970, launched on January 9, 2012, was the world's first PCI Express 3.0 graphics card. PCI Express 4.0 is expected to be finalised some time between 2014 and 2015. Reviews of the performance of PCIe 3.0 graphics cards makes it plain that the increase in performance from version 2.0 to version 3.0 is nowhere near the increase in performance between version 1.0 and version 2.0.

PCI Express -

The MSI K8N Diamond Plus Socket 939 motherboard with two SLI PCI Express slots

The image shown above is of an MSI K8N Diamond Plus Socket 939 motherboard with two x16 SLI PCI Express graphics slots for AMD Athlon 64 and 64 FX processors.

There are two standard PCI slots - the orange slot and the white slot of the same length next to it on the far top left side of the board. The PCI Express slots are two long x16 slots (the longest slots on the board) for two graphics cards in SLI mode, one yellow x4 slot and two short white x1 slots for other PCI Express devices, such as a sound card, joystick, dial-up modem, etc., which have not yet appeared on the market.

There is no AGP video slot for an AGP video card. The slots for RAM DIMM modules are the four horizontally aligned blue and teal slots in the bottom right corner of the board.

Because the present Peripheral Component Interconnect (PCI) bus has reached the limit of its safe clock rate and its data-transfer capacity, a new much faster kind of bus is required to keep up as much as possible with increasingly faster hardware.

The original PCI bus is a parallel data system that works in the same way as the ATA IDE system, which transfers data down a cable containing 40 conductors. The PCI Express bus is a serial system of the same kind as the other new systems - the USB/FireWire and Serial ATA (SATA) data-transfer systems.

The PCI Express bus improves performance by replacing the shared PCI bus with a point-to-point packet switched design similar to the kind used in switched networks. The data is transferred in packets, each one of which contains the address of its destination and is routed through point-to-point connections until it arrives.

The fundamental element of the PCI Express bus is a four-wire link between only two devices called a lane. The two pairs of wires carry single bits of data in each direction.

The smallest and slowest link is called an x1 link, which has a single lane and which transfers one bit of data at a time in either direction. An x2 link has two lanes and transfers two bits of data in each direction at a time, etc. The standard sizes of PCI Express links are x1, x2, x4, x8, x16, and x32, with the possibility of the future development of an x64 link. An x32 link has 32 lanes and so can transfer 32 bits of data in each direction at a time.

The PCI bus uses a clock signal transmitted between the devices at each end of a link, but the PCI Express bus operates at a data transfer rate of 250MB/s per lane, per direction, which is 500MB/s in both directions. That is substantially faster than the maximum clock rate of 66MHz of the PCI bus, which can transmit only a maximum of 66Mbit/s of data down each data wire. The parallel PCI bus has a maximum data-transfer bandwidth of 132MB/s, which is shared by all of the devices connected to the bus.

Note that there are eight bits in a byte of data, so a megabit (Mbit) is an eighth of a megabyte (MB).

Because each lane consists of four wires, the PCI Express bus can transfer data in both directions, which is known as full duplex. Sound cards that are full duplex allow the connection of a microphone and can send and receive sound data.

The PCI slots on a motherboard are of the same fixed size, but the slots of the PCI Express bus can vary in size.

A switch using similar technology to that used in a networking switch is built into a PCI Express motherboard. It acts like a network router by examining the data packets and then switching them to the correct link. (A network switch would switch incoming data to the correct internal IP address.)

The processor and RAM memory are connected to this central switch, which is called the root complex. The switch manages all processor and memory transfers and PCI Express links to the rest of the system, such as to the PCI and USB buses, which are linked to across special electronic bridges. There is no need for an AGP bus, because an x16 PCI Express video card is much faster than an 8x AGP video card.

The data is transmitted to the PCI Express bus by the motherboard's chipset in packets of varying sizes that match the link being used. It is then broken up and transferred down the lanes. The packets are then reassembled at the receiving end. As well as containing the address of their destination, the data packets can make use of built-in error correction technology so that if an error is detected the corrupt packet is discarded and resent. Although it works well, the technology involved in this process is extremely complex, and that is why it has taken so long to be developed.

Since the length of a PCI Express slot depends on the number of lanes it contains, an x16 slot is about the same length as a PCI slot, but x8, x4, x2, and x1 slots get progressively shorter as the number of lanes they contain diminishes.

Most PCI Express motherboards are of the kind shown above, usually having a single x16 slot for a video card, a single x1 and a single x4 slot for devices that don't require much bandwidth, such as an adapter card with the ports for a mouse and keyboard, or a joystick. Since most motherboards still have PCI slots, device manufacturers have yet to produce devices that use those two slots.

Note also that motherboards are now available that have two x16 PCI-E slots for two video cards that are linked together and use nVidia's Scalable Link Interface (SLI) technology. Information on it is provided further down this page.


There are also x8 and x12 variants that are only likely to be seen on the motherboards used in servers that don't need a monitor because they are connected to the network that they serve. Dell sells its inexpensive PowerEdge servers that have two x8 PCI Express slots that are used for high-speed Input/Output (I/O) cards such as a RAID controller for an array of hard disk drives, or a gigabit Ethernet network interface card (NIC). Some people have bought these servers thinking in error that they can be used as cheap desktop computers by fitting a video card in one of the x8 PCI Express slots. Erroneous thinking, because all PCI-E video cards require a x16 slot. There are no x8 PCI-E video cards, and there is little or no likelihood that there ever will be.

Since each end of a PCI Express bus link can negotiate how many of the available lanes will be used to transmit data, an x1 adapter card can be plugged into any of the longer PCI Express slots. In short, an adapter card can be plugged into a slot of its own size or into a longer slot, but you obviously can't install an x16 card in a short x4 slot.


Mini PCI Express is a connector designed for use in laptop and notebook computers. NewCard and ExpressCard is the PCI Express equivalent of PCMCIA cards.

The packet-switching technology of PCI Express makes it very flexible. For example, a Quality of Service (QoS) feature allows devices to negotiate a transfer priority. For example, a video stream could be granted priority over other types of data transfer and so should be able to display without any interference or glitches.

Fortunately, software compatibility with the original PCI bus has been maintained, so device drivers and operating systems don't have to be modified in order to work with the PCI Express bus. However, if the new features, such as QoS, are going to be used , the software using it has to be modified, which means that the developers will have to create upgrades, or provide updates for existing software.

It is well know that there is not much difference in the performance of 4x and 8x AGP video cards, but will there be any difference between AGP and PCI Express video cards? - Of course, but how much faster will the new cards be?

The power requirements of the power supply unit (PSU): the PCI Express power connector

If you want to install a high-end video/graphics card the +12V rail would have to deliver between 20A and 30A of current. Many PSUs deliver a maximum of under that. Therefore, you should always make sure that the PSU in a system can match the power requirements of a high-end video card before you buy or install it.

High-end PCI Express video/graphics cards have to be connected directly to the PC's power supply unit (PSU). The following webpage shows images of all of the connectors provided by a modern desktop-PC power-supply unit, including the 6-pin and 8-pin PCI Express power connectors that connect to a graphics card to provide extra power. -

The image below shows where two power connectors from the PC's power supply unit connect on an AMD Radeon HD 6790 graphics card.

Where two PCI Express power connectors from the PC's power supply power are connected  on an AMD Radeon HD  6790 graphics card

If a particular power supply unit doesn't have the required number of PCI Express connectors, it's possible to buy an adapter that is fitted to a standard Molex power connector of the kind that fits to standard IDE ATA (non-SATA) disk drives that changes it into one.

PCI Express: nVidia's Scalable Link Interface (SLI) dual-video-card technology

There is a new PCI Express technology already available called Scalable Link Interface (SLI) that makes it possible to double performance by using two PCI Express video cards on a motherboard that supports the technology.

Motherboards that can run two PCI Express video cards with graphics chips made by NVIDIA are available that run in SLI mode. ATI's response was dual-card technology called CrossFire. At first, you had to buy a motherboard that supported either SLI or CrossFire, but motherboards, such as the Intel-based Socket 1156 Asus P7H57D-V EVO motherboard, support both technologies.

SLI-capable motherboards come with a special bridge that connects to the top of each of the cards to link them. Two PCI Express cards that use the 6600, 6600GT, 6800GT, and 6800Ultra and later chipsets made by NVIDIA are required.

When the technology first became available, two identical video cards that support SLI mode were required, but that is no longer the case.

NVIDIA's Version 80 driver has made it no longer necessary to have exactly the same video cards and firmware versions. SLI mode can also now be used without having to make use of an SLI bridge connector that is connected between the two cards.

It used to be a requirement that two AMD/ATI CrossFire graphics cards had to be linked by an external cable. However, its Catalyst 5.11 drivers - and later versions - eliminate the need for this, and also eliminate having to make use of a CrossFire Master card, but at the price of reduced performance.

If you want to find out how to install two video cards so that they run in SLI mode, download the illustrated user manual for the Socket 939 MS-7100 (aka K8N Neo4 Platinum/SLI), or any other motherboard that supports SLI.

An SLI motherboard has an option in Display Properties called Enable Multiple GPU (Graphics Processing Unit). To open Display Properties, right click with the mouse on a empty space on the Desktop, click Properties, click the Settings tab in Display Properties, click on the Advanced button, and then click on the Adapter tab, which can just have the name of the SLI video cards being used, such as GeForce 6600 GT, instead of being called Adapter.

Note that if you use two high-end video cards in SLI mode that require to be connected to the power supply unit (PSU) via a PCI Express power connector, you need a PSU with two such power connectors - one for each card. If each of the cards requires two power connectors, the power supply must have four. You can have a look at the current Akasa power supplies to find out which connectors they provide by visiting that company's website.

A dual-core processor can draw up to 130W on its own, so you should find out which wattage of a power supply that will support running two high-end graphics cards. You may need a 700W or higher model. The manufacturer's website will provide the information and certified makes/models of power supply.

If you plan on using dual graphics cards that use either nVidia's SLI technology or AMD/ATI's CrossFire technology, make sure that your PC has a power supply that explicitly states in its specifications that it supports the dual-card technology that you want to install.

It is advisable to find out if a power supply has been certified for use in SLI systems by NVIDIA by visiting its website.

SLIZone - - is devoted to every aspect of SLI. You should be able to find out anything about it that you need to know, including recommended motherboards, drivers, and power supplies.

If you're having problems in getting two cards to work together, read this Q&A on this site: I can't get two SLI or CrossFire video/graphics cards to work together in my computer.

SLI mode using only one video card

It's already possible to buy a single video card with two graphics processors that run in SLI mode on a specially adapted motherboard. Benchmark tests of the following video card and motherboard combination have produced very impressive results.

The Gigabyte 3D1 video card has two nVidia GeForce FX 6600GT graphics processors, each of which has its own 128MB of graphics memory. It can only run on the Gigabyte K8NXP-SLI motherboard, which uses just one x16 PCI Express slot that is divided into an eight-lane track for each of the graphics chips.

The Gigabyte 3D1 video card can also be installed in a conventional x16 PCI Express slot, but, as might have been expected, it only functions with about half the performance.

ATI's CrossFire dual-graphics card technology

Video cards using ATI's CrossFire dual-graphics-card technology are now available.

Motherboards that can run two PCI Express video cards with graphics chips made by NVIDIA are available that run in SLI mode. ATI's response is dual-card technology called CrossFire.

At first, you had to buy a motherboard that supported either SLI or CrossFire, but motherboards, such as the Intel-based Socket 1156 Asus P7H57D-V EVO motherboard, support both technologies.

ATI (now called AMD) links its dual-card setups by using an exernal cable to link the two cards together. However, its Catalyst 5.11 drivers - and later versions - eliminate the need for this - and having to make use of a CrossFire Master card - but at the price of reduced performance.

Note that some motherboards that support CrossFire still use a video link cable to connect the two graphics cards. An example is the Socket LGA1366 MSI MS-7522 motherboard for Intel's new Core i7 quad-core processors that first became available in November 2008. An image of the cable is shown below.

Cable used to link two CrossFire graphics cards used by the Socket LGA1366 MSI MS-7522 motherboard

The CrossFire Video Link cable is required to connect the "golden fingers" on the top of the two graphics cards. Although two graphics cards are used, only the video outputs on the CrossFire Edition graphics card works, therefore the monitor must be connected to the CrossFire Edition graphics card.

The motherboard's user manual should have the installation instructions for graphics cards, memory, hard disk drives, etc., and a BIOS section that provides information on BIOS settings.

If you're having problems in getting two cards to work together, read this Q&A on this site: I can't get two SLI or CrossFire video/graphics cards to work together in my computer.

If you plan on using dual graphics cards that use either NVIDIA's SLI technology or ATI's CrossFire technology, make sure that your PC has a power supply that explicitly states in its specifications that it supports the dual-card technology that you want to install.

ATI (now called AMD) came up with a quad-chip graphics system. Read about it here:

QuadFire: CrossFire-on-a-Stick [April 2007] -,review-2135.html

The Digital Video Interface - DVI

DVI stands for Digital Visual Interface.

With the standard analog connection interface still used with most video card/monitor combinations, a computer has to convert its native digital video output to the analog video output supported by an analog CRT or LCD monitor. With DVI, everything is digital. The output from the video card is supported directly by the monitor.

The quality and speed of DVI output is superior, because there is no digital-to-analog conversion process involved.

DVI supports higher resolutions (more screen pixels). It supports high-definition video, and a bandwidth of about 165MHz - about 165 million pixels per second. The DVI is also hotpluggable (although that capability has yet to be supported by the current versions of Windows), which means that you can plug in or unplug a DVI device while the computer is running. DVI is set to become the next major video standard, and, as such, will replace all of the current standards such as SVGA.

Note that a monitor needs to have a DVI input port in order to able to use a DVI connector on a video card, which, you should also note, not all video cards have.

If anyone is thinking about buying a new flat panel LCD monitor, it would be wise to purchase a model that supports both analog D-sub VGA and DVI connectors. Otherwise, you may find yourself having to upgrade your monitor when you upgrade a video card that only has a standard analog monitor connector to one that only has a DVI output port.

All About DVI - A Complete Guide to the Digital Video Interface -

Accelerated Graphics Port: The AGP standard

Speed = frequency

Note that anything measured in Hz or MHz is measuring its frequency, not its speed - the term that is often used instead of frequency. In electronics, when the frequency is increased, the electronically generated wave pulse isn't actually going any faster - it always approaches the speed of light - it is just able to carry more data, because the wave is compressed as the frequency of the wave increases. There are more up and down cycles per metre, so the higher the frequency of a wave, the more data it can carry, in much the same way as compressed print can place more data on a page.

AGP modes

AGP 1x mode = 266MB/s (megabytes per second data transfer rate/bandwidth)

AGP 2x mode = 533MB/s

AGP 4x mode = 1.07GB/s (gigabytes per second. 1GB/s = 1024MB/s)

AGP 8x mode = 2.14GB/s

To be used, these modes of operation must be supported by the video card itself, and the AGP slot and BIOS of the motherboard.

AGP versus the new PCI Express standard

Theoretically, PCI Express video cards can provide twice the bandwidth made available by the AGP 8x architecture (up to 4 GB/s with an x16 PCI Express slot), which allows greater bandwidth for future games and video-rendering applications. Moreover, the PCI Express x16 graphics standard is capable of providing greater power to a video card than the AGP 8x standard. However, because of the high number of PC still using it, the AGP standard is not dead yet.

Make sure that the AGP slot on the motherboard supports at least AGP 4x or it will probably not be able to supply the correct voltage for the current gaming video cards. Only ATI/AMD Radeon and NVIDIA GeForce cards should be considered for gaming purposes. AGP 8x is the latest standard, but an 8x card will almost certainly work on a motherboard that supports only up to 4x, but if the motherboard only supports 2x it is unlikely to fit the motherboard, because AGP slots are keyed so that only the kind of AGP card that will run in a particular AGP slot can be inserted into it. Many recent motherboards that support 8x mode,also support 4x mode, but don't support the earlier 2x mode, so even if a 2x graphics accelerator, such as a nVidia TNT2 card, fits into such a motherboard's AGP slot, it won't work, and you probably won't be able to see anything on the screen at start-up.

AGP compatibility is discussed in the next item on this page.

If it uses AGP, you can find out which AGP standards are supported by your computer's motherboard by looking in the BIOS, or by consulting the motherboard's user manual, which can be downloaded from its manufacturer's website in the PDF format if you don't have a printed copy.

Keep reading this article for more information on the AGP standards.

Benchmark tests

If you want to run benchmark tests on the processor, RAM, video/graphics card, and hard disk drive, download PCMark04 from

AGP compatibility

AGP Version
Maximum Bandwidth/Transfer Speed
AGP 1.0 3.3 Volts 1x at 267MB/s, 2x at 533MB/s
AGP 2.0 1.5 Volts 1x at 267MB/s, 2x at 533MB/s, 4x at 1067MB/s
AGP 3.0 0.80 Volts 4x at 1067MB/s, 8x at 2133MB/s

The AGP 1.0, AGP 2.0, AGP 3.0, AGP Pro standards, and 1x, 2x, 4x, and 8x video cards, and the different voltages they support, make AGP compatibility a somewhat confusing subject.

Read this Q&A on this site - The voltages used by the different kinds of AGP video cards. Use your browser's Back button to return here.

Visit these two pages for illustrated information on AGP compatibility:

If you have, say, a relatively elderly dual-voltage AGP 2x card the keys of which fit the AGP slot of a new motherboard that only supports, say, 8x cards, it won't damage the motherboard, but it also won't work.

Therefore, always check the motherboard's manual, which can usually be downloaded from its manufacturer's site, to find out what kind of video cards it supports before you try installing relatively elderly video cards.

If the motherboard only supports 8x video cards, then the BIOS won't support the lower speeds, because the BIOS is customised to support the motherboard's design features.

Is there space in the case for an upgrade?

You must make sure that you have enough space around your motherboard's PCI Express slot(s) or AGP slot if you want to install some of today's gaming video cards, because they often have large cooling units that will make it impossible to use the PCI slot beside the graphics slot(s). Hard disk drives and filled DDR RAM DIMM slots can also get in the way. The nVidia GeForceFX 5900 range of cards in particular are very large. Also note that the 256MB versions of most cards are larger than the 128MB versions. If you are unsure if a particular card will fit in the space provided by you computer, it would be best to take the tower unit into the shop from which you are buying it and have it fitted there.

Go to Page 2 of this article for information on removing and installing a video/graphics card.

The warranty periods for other computer components such as video and sound cards, etc.

If you purchase computer components, such as a video card, sound card, modem, network card, power supply unit, etc., it is usually provided with a warranty that lasts only a year (twelve months).

Most video-card manufacturers provide a one-year or two-year warranty for their products, but it is worth noting that Asus, Leadtek, PNY, Gainward, and MSI provide excellent three-year warranties.

There are also some manufacturers of video/graphics cards, such as PNY, that offer an extended warranty on their cards if the buyer registers it on their websites.

Note that if a component such as a high-end video card dies within its warranty period, the manufacturer (or the vendor if it is an OEM card supported by the vendor instead of the manufacturer) can make you prove that you have taken adequate precautions to keep the computer's case cool before it honours the warranty. That probably means having to provide photographs of the inside of the case that show the case fans that have been installed. Therefore, you should obtain and read the warranty's terms and conditions before you make a purchase to find out what is involved in making a claim against it.

There are other exceptions, such as RAM memory modules, for which a manufacturer such as Crucial provides a lifetime warranty. That means that it is covered by the warranty as long as the purchaser uses the memory in a computer that supports it. That amounts to about five years, because new types of RAM is always being released, and the older modules won't be supported by new motherboards. However, note that generic (unbranded) memory modules are only covered by a twelve-month warranty period.

See the Warranties page on this site for more information on them.

Low-profile video cards

Slimline ATX desktop and tower cases are far too confined to house standard full-sized PCI or AGP or PCI Express video cards, therefore video cards that are usually half the full-size height, called low-profile cards, have to be used.

Proprietary manufacturers such as HP, Compaq, Gateway, and Dell can use slimline cases. Examples of models that can use them are the Compaq DeskPro and the Dell Optiplex.

PCI/AGP/PCI Express video cards are made as low-profile cards, and they are usually not much more expensive that the full-sized version of the same model, but availability could be a problem, because, firstly, not all video-card manufacturers make low-profile cards, and, secondly, when available, they have the same names as their full-sized counterparts, and, if not purchased at a premium from HP, Compaq, Dell, etc., would therefore be difficult to locate. Moreover, as you might expect, low-profile cards are never as powerful as the full-sized models.

The technology provided by the latest video cards cannot currently fit on to low-profile cards, so instead of running a 256MB ATI Radeon 9800XT or nVidia FX 5900 card, the user with such a slimline case would only be able to use relatively under-powered low-profile cards such as a 128MB ATI Radeon 9200 or an nVidia GeForce FX 5200.

Moral of the story: avoid buying a computer housed in a slimline case.

PCI version 3 (PCI Extended - PCI-X/PCIx)

21 April 2004 - The PCI Special Interest Group announced the release of version 3.0 of PCI (the Peripheral Component Interconnect standard), known as PCI Extended (PCI-X) to distinguish it from the current PCI Express video/graphics standard that is covered further down this page.

If you see PCIe or PCI-E shown in the specification list of a computer or motherboard this stands for PCI Express.

Don't confuse PCI-X (or PCIx) with the PCI Express standard, because it stands for PCI Extended, which is an much improved extension of the PCI standard that is fully backwardly compatible with the previous versions of the PCI standard.

The new PCI standard migrates from supporting 5V to using 3.3V, which current PCI adapter cards use. However, PCI cards that are keyed to use both 5V and 3.3V continue to be supported.

Internal and external TV tuner cards

Click here! to go to the information on this subject on Page 2 of the Video and Graphics section of the site.

Cooling units, device drivers, and the video-card BIOS

If you purchase a retail (boxed) video card, it will come with all of the cables it has ports for, its software device drivers, and will also probably come with a heatsink and fan unit that cools the main video chip. This will not necessarily be the case with an OEM video card that is supported by the vendor but not the by the manufacturer. OEM video cards can be sold alone, without a cooling unit. If that is the case, you'll have to purchase the cooling unit separately. Remember that not all video cards require special cooling. Seek advice about cooling if you purchase an OEM video card that doesn't come with a cooling unit.

In any case, if the video card uses a chipset made by one of the major manufacturers, you will be able to download the latest driver file from the relevant website. Indeed, the chipset manufacturer's drivers are often superior to those provided by the manufacturers of video cards that incorporate those chipsets into their video cards.

You should upgrade all of the computers device drivers as often as possible (especially if you upgrade any of the other graphics drivers used by your system) in order to keep them compatible. For instance, you might install the latest version of the DirectX gaming software, which might then conflict with the older drivers being used by your video card. Or you might update the motherboard's chipset driver, made available from the computer's motherboard's site, which then conflicts with an old graphics-card driver, etc.

Video cards featuring home movie video editing and connectivity to VCRs and camcorders

You can purchase video/graphics cards that are very reasonably priced and which allow a user to edit movies, connect to video recorders (VCRs) and camcorders, and support DVD authoring and burning. If you want any of those feature, look for them in a particular card's specifications.


See the Monitors section of this website for information on analog and digital LCD and CRT monitors.

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