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Desktop PC Cases and Case Fans - Page 2


Page 1 - The motherboard (mainboard) used in desktop computers

This page - Desktop PC ATX cases and case fans

Page 3 - The Power Supply Unit (PSU) used in desktop computers, making a good choice of motherboard, etc.

Page 4 - Sundry useful motherboard information


Click here! to visit the page on this site devoted to motherboard and power supply problems and their solutions.


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

ATX desktop PC case with transparent side

The PC case with its power supply unit (PSU) are crucial components whose importance is often overlooked. This is a serious oversight, because the case (with its power supply) is as important to a PC's stability and performance as its RAM memory, motherboard and processor. The case should be well designed so that it is quiet (has no whining fans) and keeps the internal hardware adequately cooled. The case should also provide easy access to its components so that it is easy to work on.

A power supply unit (PSU) often comes with an inexpensive PC case, but most PC cases come without a power supply, especially expensive cases, requiring the power supply to be purchased separately. In most cases, the power supply that comes with a case is underpowered and/or of poor quality should be replaced due to the fact that if the power supply fails, it can take the other components to component heaven with it.

You should always make sure that a power supply that is provided with a case or a new PC desktop is a quality unit capable of delivering its stated maximum power output (400W, 500W, 600W, etc.). The power supply unit installed in inexpensive PCs and cheap cases is almost always a cheap, low-quality unit that should be replaced for the good of the computer, which can be destroyed if the power supply packs in. Note well that cheap power supplies are also a fire hazard. To find out the make/model of power supply requires opening the case and reading what is written on it, because that information is very seldom provided in the machine's specification list. You can then use the make/model as the search term to conduct a web search. I would advise doing that as soon as you receive a new desktop PC regardless of its cost, just in case a cheap power supply is installed. In any case, it is quite possible that an expensive PC might have originally have had a quality unit that was replaced by staff working at the store with a cheap unit.

Cases come in several different sizes and types - mini-tower, midi-tower, full tower and desktop (the case lies horizontally on the desk instead of vertically like a tower case). Since most users don't require anything more than a midi-tower case, it is the type most commonly used in the construction of a personal computer.

Most of the current PC cases have some tool-free features, such as clips that retain adapter cards, thumbscrews for the side panels, and tool-free drive bays that have plastic rails that clip to the side of the hard disk drive(s) and CD/DVD drive(s).

The description of a motherboard that indicates its type is called its form factor.

More information will be provided in this article and others on this site, such as Build Your Own PC, but if you want to read technical information on the different form factors, visit

AT (redundant technology, long gone) and ATX cases and motherboards are the most common types used in personal computers.

AT cases and motherboards have been superseded by the ATX standard, which, was expected to be superseded by the BTX standard that Dell already uses for all of its Intel-based desktop PCs. However, that succession has not happened and the ATX form factor is still king.

The main form-factor motherboards in use are ATX and micro-ATX are fitted into mini-tower (aka micro-ATX), midi-tower and full-tower ATX cases. Both full ATX and micro-ATX motherboards are powered by ATX power supply units (PSUs). Micro-ATX motherboards are smaller than full-sized ATX motherboards and so cannot provide as many adapter-card or RAM-memory slots, can be installed in any ATX case, but are usually installed in mini-tower ATX cases. A full-sized ATX motherboard is too large to be installed in a mini-tower (micro-ATX) case. Here is a recent review of a mini-tower case:

Antec Mini P180 review -

ATX [form factor] -

Cable management is an important factor because cables can restrict the airflow inside the case. Cases that are well designed provide holes that are used to route cables behind the tray that the motherboard is installed on and away from the fans. When you look inside the case of a brand-name PC, you will see that the cables are tied together and routed in order to provide as much unrestricted space inside the case as possible. If you are building a PC, you should do likewise.

Many cases now provide tool-free access by using thumbscrews that can be removed by hand instead of by using a screwdriver and removable drive bays.

Home Theater PC (HTPC) cases, which usually lie horizontally as opposed to vertically, can usually accommodate standard ATX components, so it isn't necessary to buy specially-sized motherboards or half-height adapter (video, sound, etc.) cards.

An article on Tom's Hardware Guide, made available on December 6, 2005, called Either Way ATX or BTX Cases, which was still available in February 2008, discusses both types of PC case. -,1187.html

Note that Antec, Cooler Master, and Silverstone manufacture cases and power supply units.

Small Water Versus Big Air, Part 3: Cooling Questions Answered -

"Parts one and two of our air and self-contained water cooler reviews compared components on an open bench with each model's included fan. Understanding that performance will differ in an enclosure, what happens when we install these solutions in a case?" -,review-31974.html

Part 1: Four Gaming Enclosures Under $50 (August 2010) -

"Sometimes, overclocking is the key to getting budget hardware humming along at enthusiast-class performance levels. But getting there requires extra cooling. Today we're examining the performance of four low-cost gaming enclosures under $50 bucks." -

Three Gaming Cases, With Power, Under $100 (July 2010) -

"Case and power supply combos always look like a bargain, but bargain-basement parts have always seemed to chase experienced builders away. Today, we consider three budget-enthusiast models to determine if any of them can meet our basic gaming needs." -,review-31936.html

Roundup: Four Gaming Cases Under $150 -

"Several vendors market their enclosures specifically toward gamers, but nobody has really defined what makes a gaming case. We take a look at examples from Cooler Master, NZXT, Thermaltake, and Zalman with the aim of shedding more light on this segment." -,review-31843.html

Five Gaming Enclosures [PC Cases], Rounded Up -

"The cases in this roundup range in price from $120 to $400; these are not your $49, low-end, plastic chassis. All of them feature several fans, but I still tested their cooling abilities on a fairly standard Core i7 setup. Of course, to really throw in a challenge, I added a ridiculously hot graphics card (an ATI Radeon HD 4870 X2-based card from Asus), as if any number of fans can keep that monster cool." -,review-31700.html

Corsair fire a broadside at the chassis guys [video review high-end water-cooled case] -

ATX desktop PC case with its side panel removed

In the image above of an ATX case, with the motherboard, memory modules, hard disk drive, graphics card and wireless network card installed, you can see the power supply unit (PSU) in the top left corner, above the motherboard, the ports panel of which can be seen from the inside view. An internal fan can be fitted just under the power supply unit over the outlet there for such a fan.

The ports panel is where the ports that are built into an ATX motherboard come through to the back of the case.

The image below shows the back of the same ATX case. The ports panel (covered by an I/O plate) shows where the ports on the motherboard are coming through its cutouts. The blue port is an analog VGA port for the graphics chip integrated on the motherboard to which a monitor is connected.

The back of an ATX desktop PC case showing its adapter slots and ports panel

This is a standard midi-tower ATX case. PCI and PCI Express adapter cards will be fitted into their slots on the motherboard so that their face plates and ports appear through the four horizontally-aligned openings that are under the motherboard's ports panel. You should be able to see that a sound card's face plate with its five round plug holes and below it a wireless network adapter card with its two antennas, both of which are installed in PCI slots on the motherboard (as can be seen in the image of the opened case above).

The image below shows a close-up view of the ports panel's I/O plate (far right) that is provided with a PC case, and with most new motherboards.

The I/O plate or ports panel (far right) fitted into the back of a case to accommodate the ports on a motherboard

In this example, there are no removable metal covers over the I/O plate's cut-outs, because the ports panel came with a motherboard, the ports of which fit into all of the cut-outs. The ports are, from top to bottom and left to right, three sound ports for the inbuilt sound capability, a FireWire port, four USB ports, a legacy parallel port, two legacy serial ports, and PS/2 mouse and keyboard ports.

The I/O ports plate that is provided with a case will probably have removable metal covers, because outlets for more ports, such as a video port where the motherboard has an inbuilt video capacity, will be provided. If you fit a motherboard that doesn't use any of the extra port outlets, they will remain covered, and therefore won't affect the cooling of the case by leaving holes.

Note that not all of the cut-outs in the ports panels match when comparing those of the two images above. Only the three central cut-outs for a legacy parallel port and two legacy serial ports match. You should therefore always make sure that you will be getting the I/O plate for the ports panel when purchasing a second-hand motherboard, because the one already fitted into your case might not be able to accommodate the replacement motherboard properly.

When installing a new motherboard, you would remove the existing I/O ports plate in the case, and replace it with the one that came with the new motherboard.

The image below is of a ports panel that comes with a motherboard. The ports on the motherboard fit through the openings when the panel is fitted into the back of the case. The two openings on the far left are for PS/2 keyboard and mouse connections, and the three openings on the far right are for the sound connections, with the LAN networking and USB ports beside them.

The ports panel that fits in the back of the PC case, through which the ports on the motherboard appear

Front-mounted ports

Most current PC cases provide USB (USB 2.0 and USB 3.0) and audio ports from the front of the case that are usually concealed behind a panel. An eSata port (for an external SATA hard disk drive or CD/DVD writer) and FireWire ports provided at the front of the case were more common at one time but are now rarely provided. USB 3.0 support is now provided by most motherboards, on the main ports panel that appears at the back of the case when the motherboard is installed and headers on the motherboard, but, by April 2012, very few cases provided USB 3.0 ports from the front of the case that provide the cables to connect them to those headers.

In order to be used, the motherboard must provide the headers that their cables connect to. The motherboard's user manual, which is can be downloaded from its manufacturer's site, should provide you with the information on where the headers are located on the motherboard.

If the headers are provided by the motherboard for the front-mounted ports and one or more of them don't work, check the motherboard manual for a jumper setting that enables them.

PC case fans

120mm PC case fan

If you buy a brand-name PC it will come with one or more case fans that should be adequate to keep the interior of the case cool enough so that the processor's cooling system (heatsink and fan or water cooled) can function optimally. Most cases provide two case fans, an intake fan at the front of the case, which draws air in, and an exhaust fan at the rear of the case, which expels the hot air.

If you are building a desktop PC, the case you choose will have at least one case fan, but you can install more if the case has additional mountings. If you do, you must make sure that the fans compliment each other (don't fight against each other). If one side of the case is transparent, you can test the airflow by blowing some smoke into the case to see how the air is being expelled.

Making a choice of fan is not as easy as it might appear to be. Desktop PC cases usually come with the mountings for two sizes of fan - 80mm and 120mm fans, so you have to find out which mountings are available before you make a purchase if you are adding extra fans. 120mm fans are usually more silent than 80mm fans. 120mm cases are the most common type in use, but 140mm, 180mm and even 200mm case fans are available.

Some cases come with the holes for the pipes used by a water-cooling unit, but they are not common. If you want to install water cooling, you should buy a case that is designed for that type of cooling otherwise you will have to adapt the case yourself.

Note that water-cooling systems are usually large, taking up plenty of space. Consequently you have to buy a case with sufficient space to install one. Such cases have been scarce since water-cooling devices first became available, no doubt because not many people use them. As might have been expected, since not many of them are sold, the cases capable of housing a water-cooling system are not cheap. The following article deals with the type of case that is required, ranging in price from £150 to a staggering £323:

Four ATX Cases For High-Capacity Water Cooling, Reviewed -,review-32399.html

If you purchased the case separately, it should have come with a user manual that will probably also be available as a download from its manufacturer's website if you can identify its make/model. It will tell you the sizes of the available mountings. Alternatively, you can open the case and measure the fan mountings. Some cases are difficult to open, you may need to remove the front cover instead of a side panel, etc., so you should consult the manual if you can't determine how to open a particular case.

Where possible, you should use 120mm fans, because they move more air while spinning slower and therefore usually make less noise than 80mmm fans.

Most online and retail PC stores sell case fans. It is always a good idea to find and read the available reviews on the web of any kind of computer-related purchase before you part with your money. You can make use of a search engine to find reviews by using the product's name plus the word review. Here is a page reviewing 120mm fans:

SPCR's Fan Round-Up #2: 120mm Fans -

Some cases have been designed for maximum noise reduction. They usually have sound-reducing foam on each of the side panels, which increases insulation resulting in poorer cooling that might have to be countered by installing one or more additional fans. The best cases provide sound dampening that can be replaced or have the capacity to be countered with extra fans if necessary.

Case modding

Case modding is term used to describe adding all kinds of fancy add-ons and gizmos to a computer case. You can add fancy coolers, fans, fan controllers, neon lights, etc., and you can buy fancy cases that have exotic features such as see-through areas so that you can see inside the case, etc. The following forums have a case-modding forum. Forums -

UK-specific sites that offer offer case modding equipment are:

US-specific sites are: and

Others can be found by entering a search term such as "case modding" + uk (or + us) or just case modding forums in a search engine.

Motherboards that use riser cards for the PCI and AGP adapter cards

If the openings for the ISA, PCI or AGP adapter cards are aligned vertically instead of horizontally at the back of the case, then the case is a non-standard ATX case that makes use of a riser card that is fitted to the motherboard.

Instead of the motherboard, the riser card contains the slots for the ISA, PCI, or AGP adapter cards. Therefore, the motherboard will also be a non-standard ATX motherboard, because it will have no slots for adapter cards.

The ISA, PCI, and AGP slots on the riser card are arranged so that when an adapter card is fitted to it, it will run parallel to the motherboard. That means that the openings at the back of the case for adapter cards will be vertically instead of horizontally aligned if a riser card is used.

The use of a riser card makes it possible to use slimmer cases, because vertically aligned openings take up less width than horizontal openings. But riser cards for adapter cards often block the free circulation of air inside the case, therefore often requiring the installation of one or more extra cooling fans.

The design of the motherboard for installation in a desktop or tower case will determine what a riser card looks like and how it fits into the motherboard and the case.

Non-standard ATX cases and motherboards that make use of riser cards should be avoided if you want to upgrade or add functionality to a PC with standard adapter cards

Note that using a riser card can often solve the problem of having a lack of space in the case for the installation of, say, a video card:

"As I was staring at a dismantled Toshiba Magnia SG20 appliance in hopes of upgrading the CPU, I had it stuck in my brain that I needed a specifically designed AGP video card that would fit into the tight quarters. Later, it dawned on me that there are all sorts of riser cards made for just this sort of situation. They aren't terribly expensive, and come in hundreds of flavors. A search engine is your friend. As an example, I found one page with just the right item for $15.00. They sell cards that are configured so the card can be installed on either side of the AGP slot, depending on the need, and there is a choice of 3.3V, 1.5V or universal models, [see the Video Problems page on this site for more information on video-card voltages] which is an important consideration to be sure that the card fits into and talks to the slot properly." - From the defunct Lockergnome Tech Specialist newsletter.

Note that many motherboards have the AGP slot positioned so closely to the DIMM RAM slots that the RAM modules have to be removed before the video card can be installed, and the video card has to be removed in order to remove or add RAM modules. It is not unusual to hear that someone has tried to install a GeForce 4 video card and the installed RAM modules have knocked off some of the card's protruding capacitors, thereby rendering it useless. This situation would not have been a problem if the obvious and necessary installation procedures were taken.

Low-profile video cards

Click here! to read about the half-sized low-profile video cards used in slimline desktop and tower ATX cases in the Video and Graphics section of this site.

Furthermore, very often the first PCI slot on the motherboard is positioned too close to the AGP slot. If an adapter card is installed in that PCI slot, it would deprive the AGP card of air, and might cause it to function abnormally, or be damaged by overheating.

Some motherboard reviews provide useful information of that kind.

Personally, I would not purchase a motherboard until I had read all of the reviews of it on the Internet or in computer magazines.

Heatsinks on the motherboard's voltage regulators

Modern motherboards run processors that have reached ultrahigh frequencies measured in GHz (1 gigahertz = 1000 megahertz).

Components on the motherboard get hot, and, as a result, can fail or have a reduced life expectancy, but not all motherboard manufacturer's cover the vulnerable components with heatsinks that serve to keep them cool. This could be a deliberate policy to reduce costs and introduce a limit to the product's life expectancy.

However, some motherboard manufacturers do cover these vulnerable components with heatsinks. If you purchase a motherboard that does not have these heatsinks in place, you can purchase them yourself from some computer component stores, but you would have to go to all the trouble of finding them. A better solution would be to purchase a motherboard that comes with them already fitted.

Page 3 - The Power Supply Unit (PSU) used in desktop computers, making a good choice of motherboard, etc.

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