The Build a PC pages on this site contains information on how to build a computer from its components.
Click here! to go directly to information on the first Build Your Own PC page on this site about taking the precautions you must take against static electricity before you install a computer component. Use your browser's Back button to return to this page.
Note that unlike most other hardware components, RAM memory does not require a device driver to be installed in order to function. All you have to do is install it and Windows, or any other operating system, can use it if it is compatible with the motherboard that it is installed in.
The computer must be switched off or have the motherboard's power plug disconnected when installing RAM memory modules. The power plug to the motherboard is the one that connects it to the PC's power supply unit. If the motherboard is powered when installing memory, both the memory module(s) and the motherboard can be rendered useless.
Click here! to go directly to the Disclaimer on the same page. It contains other important information that you should be aware of before working on a computer. Use your browser's Back button to return to this page.
Click here! to visit the page on this site devoted to RAM memory problems and their solutions.
Click here! to go to the information on this page on flash memory and USB flash drives.
Below is the kind of warning that is provided in the memory-installation section of a motherboard manual. The same information applies to the installation of DDR3 memory.
The image below shows two DIMM modules with heat spreaders (passive heatsinks) on them installed on the motherboard with two DIMM slots left empty. The slots are colour-coded so that the modules can be run in dual-channel mode when installed in the correct slots. Dual-channel and triple-channel modes were explained in the first part of this article. Note that Intel-based motherboards, like AMD-based motherboards, now only use dual-channel mode. Some Intel-based Socket LGA1366 motherboards and the onboard memory controllers of the Intel processors can use them use triple-channel mode, but they are so rare that memory reviews only review dual-channel (dual-module) memory kits.
You should consult your PC's motherboard manual to find out what the colour coding means and to find out which type(s) and capacities of memory are supported. Any motherboard manufacturer's site should provide manuals for its motherboards that run Intel and AMD processors. If you don't know the make and model of the motherboard installed in your computer, here is a good free utility - Belarc Advisor - that creates an analysis of the hardware and software on a personal computer. Look under FREE DOWNLOAD - belarc.com. Another utility that also provides information on the motherboard and the memory is CPU-Z from cpuid.com. You can then locate the manufacturer's site by making use of a search engine.
Assuming that RAM has been purchased that is supported by the motherboard, installing the DIMM (Dual In-Line Memory Module) modules, that have been used in all new computers since 1999, is merely a matter of opening the clips on each end of each DIMM slot and then pushing the module directly down into the slot as shown in the diagram below. Note that the notch(es) along the connector edge of the module must match the divisions in the slot. The two clips automatically close to capture the module securely in the slot, but you should make sure that they are clipped over the sides of the module.
To remove a module, just open both of the clips (push down on both clips) at the same time to release the module.
Depending on its architecture, there will always be at least one notch in a RAM module, but never more than two. The SDRAM module below has two notches, but a DDR DIMM module (below that) will only have one, and a RIMM module (used only in motherboards designed for Pentium 4 processors) has two closely-spaced notches. A DDR, DDR2 and a DDR3 DIMM module has only one notch.
The latest type of DDR memory is DDR3, a module of which has the same physical dimensions as a DDR2 DIMM module. However, a DDR3 module has its single notch in a different position to the position of the notch on a DDR2 module. Therefore, a DDR2 module cannot be fitted into a DDR3 memory slot on the motherboard, and a DDR3 module cannot be fitted into DDR2 slot. Likewise, DDR2 or DDR3 modules cannot be installed in DDR memory slots on a motherboard, and vice versa.
Note that you should consult the motherboard's manual to find out if the slots have to be filled in a particular order of rank. Some motherboards require that Bank 0 be filled first, followed by Bank 1 and 2, etc., while some motherboards allow any bank to be filled, or certain banks to be filled by different numbers of DIMMs, etc.
Note well that (if the motherboard supports it) to function in dual-channel mode, DDR and DDR2 RAM modules have to to be installed in pairs (preferably pairs matched by make and in size). Three matching modules of DDR3 memory have to be installed in the motherboards that support triple-channel mode in order to make use of that mode. If only two matching modules are installed in the correct slots in a motherboard that supports triple-channel mode, it will run in dual-channel mode.
If you want to read the information for a motherboard that supports DDR2 RAM in dual-channel mode or DDR3 memory in triple-channel mode (only used on Intel-based Socket LGA1366 motherboards by the Intel processors that use that socket), download a user manual for one of the latest products from msi.com.
Note well that some motherboards can have DIMM slots for DDR and DDR2 memory or DDR2 memory and DDR3 memory. You will probably only be able to install one type, not both. Here is an extract from the user manual of a motherboard that has separate slots for DDR memory and DDR2 memory but only supports one type at a time.
Click here! to go to the information on DDR/DDR2/DDR3 RAM on Page 1 of this article.
If you need additional information on how to install RAM in a desktop PC and Laptop PC, visit these pages:
How To Install Desktop Computer RAM Memory [Video] -
Installing a DIMM [memory module] in your desktop [PC] [Illustrated article] -
The next item on this page deals with installing memory in a laptop PC.
Using the search term dual channel ddr as the search query in a search engine will bring up plenty of links to sites and pages with information about this mode of operation of DDR RAM. Changing the search phrase suitably will bring up links to the other types of DDR RAM DDR2, DDR3.
In a desktop computer a memory module is called a DIMM (Direct In-Line Memory Module). In a laptop and a netbook computer a memory module is called a SODIMM (Small Outline Direct In-Line Memory Module). Installing memory or removing it in a laptop/netbook computer is a very simple matter that involves taking a few precautions.
SODIMM modules come in exactly the same types as standard DIMM modules and have one or two notches that key it so that only the correct type of module can be installed in the laptop's memory slots. The image below shows a Crucial SODIMM module that has one notch, which all current modules now have, in its bottom edge that keys it so that it cannot be fitted into the wrong kind of memory slot. You will be able to see where the notch is in the memory slot.
Most laptop/netbook PCs have a removable panel on the bottom that allows access to the memory module(s). The user manual that came with the computer will show you which panel to open, how to open it, and how to install a memory module.
Note that before removing or installing new memory in a free memory slot, it is advisable to remove the laptop/netbook's battery according to its user manual and then press the power button to discharge any electricity in the machine.
You should also earth yourself by touching something that is metal and earthed, such as the desktop case of a desktop PC that is connected to the mains, or a radiator, before you touch a memory module to discharge any static electricity in your body that can destroy memory modules. The metal you touch must be earthed by wiring or by touching the ground.
With some notebooks, the keyboard has to be lifted in order to reveal the panel that has to be removed in order to access the memory modules. In some laptops the entire bottom panel has to be removed to access the memory modules. But in most recent laptops/netbooks all you have to do is remove the cover from the memory bay by removing one or more screws as instructed in the computer's user manual.
Memory modules in a laptop/netbook computer lie flat in order to fit into the slender case. You usually have to hold the module so that its at a 45 degree angle in order to insert it into a free memory slot. Note that as with installing a module in a motherboard's memory slots in a desktop PC, the notch(es) along the connector edge of the module must match the division(s) in the slot. The image of a laptop memory module shown above has one notch along its connector edge that has to fit over a division within the memory slot that supports that type of memory. You then push the module into the slot at an angle of 45 degrees and then press the module down gently until it lies flat and the small clips on each side of the slot engage with it on both sides. To remove a module, push the clips on each side that are holding it in place away from it and it should automatically lift itself up to an angle of about 45 degrees and can then be slid out of its slot.
Here are some illustrated articles and videos on this subject:
Installing a SODIMM in your [laptop] notebook [Article] -http://www.crucial.com/uk/install/sodimm.aspx
How to Install Memory (RAM) in a Laptop / Notebook [Video] -
You can find plenty of other guides by entering install ram laptop as the search query in a search engine.
The following free utilities can test your system's RAM, which must be operating 100% all of the time or serious data corruption and/or system failures (that can be very difficult to track down) will occur.
Note that they take a long time to go through their various tests. As long as you can boot the computer from a floppy disk or CD, if you copy the utilities to such a disk, you can run the diagnostic tests.
Microsoft Windows Memory Diagnostic utility -
"The Windows Memory Diagnostic tests the Random Access Memory (RAM) on your computer for errors. The diagnostic includes a comprehensive set of memory tests. If you are experiencing problems while running Windows, you can use the diagnostic to determine whether the problems are caused by failing hardware, such as RAM or the memory system of your motherboard. Windows Memory Diagnostic is designed to be easy and fast. On most configurations, you can download the diagnostic, read the documentation, run the test and complete the first test pass in less than 30 minutes." - Obtain the full instructions and download from this page. -
Windows Vista and Windows 7 installs the Windows Memory Diagnostic as a startup option that is available as an option on the Windows Boot Manager screen that presents itself automatically on a multi-boot system in which more than one version of Windows or another operating system, such as Linux, is installed.
Note that the easiest way to bring the Windows Memory Diagnostic up in Windows 7 is to enter the words memory diagnostic in the Start => Search programs and files box to be presented with a clickable link.
If a system only has Windows Vista or Windows 7 installed, you can bring the Windows Boot Manager up by following these instructions:
1. - With the computer switched off (not in Standby), press and hold the F9 key.
2. - Switch the computer on while continuing to press the F9 key. Only release the F9 key when the Windows Boot Manager menu appears. If Windows Vista/Win7 starts, or comes out of Standby, select Shut Down from the Start menu, and repeat steps 1 and 2.
3. - You press the Tab key to highlight the Windows Memory Diagnostic Tool, and then press Enter. The Windows Memory Diagnostic Tool should start checking the computer's RAM memory. You can press the F1 key to review or change memory test options, and press the ESC key to interrupt the memory test. After the memory test has been completed, Windows Vista/Win7 will start automatically. An error report appears in the System Tray/Notification Area. Click on it to read the results of the memory test.
It is possible to run Windows Memory Diagnostic without
installing Windows Vista/Win7. To run the memory diagnostic,
insert the Vista/Win7 installation DVD into the computer's
DVD drive and reboot. When you get the prompt "Press any key to
boot from CD or DVD..." press and hold the space key or tap it
multiple times. This should bring up the Windows Boot Manager screen
that lists Windows Memory Diagnostic as an advanced tool.
Press the Tab key to select Windows Memory Diagnostic and
then press the Enter key to run it. After the Windows Memory
Diagnostic has finished running, the computer continues booting
the Vista installation DVD, which you can abort.
If you want to run benchmark tests on the processor, RAM, video/graphics card, and hard disk drive, download PCMark04 from http://www.futuremark.com/
If you want a quick way to identify a PC's processor, motherboard, and RAM, the free CPU-Z is ideal. It provides plenty of information on those components in Windows 95/98/Me/XP/Vista and Windows 7. Download and install the program, and look under its Memory and SPD tabs.
"It was not uncommon for an old 808x system to run off of a 95W PSU [power supply unit]. Today's computers are using at least 300W and for some duallies [dual-processor systems] 400W and up. While the CPU [processor] is the most obvious source of power consumption there is one other device in your system that can get greedy quick. RAM. More specifically, slots loaded with the latest, greatest, and fastest DDR you can get, or what your board says it will support."
The faster the RAM, the larger the capacity of the modules, the more power it needs to draw - and the modules from different memory chip manufacturers have different power requirements.
DDR, DDR2 and DDR3 RAM never works as fast as the theoretical speed ratings. As with wireless network devices, a memory module always runs slower than its ratings indicate. Moreover, remember that it's possible to use faster memory than a system supports. E.g., DDR400 DIMM modules can be used in a system that only supports DDR333 modules. The DDR400 modules will operate at DDR333 speeds. Likewise it's possible to put DDR2-667 modules in a computer that only supports DDR2-533 modules.
Overclocking means setting the components in a computer to run faster than their official tested and specified speeds.
The RAM's clock speed expressed on MHz should be equal to the speed of the motherboard's FSB in MHz, otherwise the RAM is being underclocked or overclocked . So, if a particular motherboard has an FSB of 200MHz, it should use DDR400 RAM, which is designed to work with an FSB of 200MHz. But if DDR533 RAM, designed for use on an FSB of 266MHz, is installed, it will run on an FSB of 200MHz, and if the motherboard supports increasing the FSB, you can overclock the FSB up to at least 266MHz, depending on how high the motherboard's BIOS settings or jumper settings (used on older motherboards) go.
Using RAM modules which have a higher speed rating than a system is designed to use obviously makes it easier to overclock the motherboard's system bus - the FSB - significantly, because increasing the FSB overclocks the RAM. If, say, the system had DDR333 modules that are designed to run on an FSB of 200MHz, the modules might or might not run on an overclocked FSB of 225MHz. But if DDR400 modules were installed, they would be more likely to run at the higher FSB.
The CAS latencies - the properties of the RAM that delay or slow its operation down - are expressed as a string of numbers such as 2-2-2-5 (fast) and 3-4-4-8 (slower). You don't need to know what the latencies are; you only need to know that the lower the latencies are, the faster the RAM is. But the figures are in microseconds, so there isn't much noticeable difference in the speeds of RAM with the latencies provided above, and this is borne out in benchmark tests. However, if the RAM has low latencies it is likely to be more overclockable than RAM with higher latencies, because, increasing the latency settings in the BIOS (increasing the delay of the latencies) usually makes it easier to run the RAM on a higher FSB.
If your computer has low-latency memory modules, to make sure that they've been detected correctly, enter the BIOS setup program. The RAM settings are usually on a page in the BIOS called something like Chipset Features Setup. If there is an option called SPD (Serial Presence Detect), enabling it makes the BIOS set the optimal timings automatically. SPD refers to a small chip on each memory module that holds the latency settings information. Note that the BIOS doesn't always read the information properly. If you suspect that to be the case, you can set each of the values manually in the BIOS. The lowest presented settings are the fastest, not the highest, because the settings are for timings and the lower the timings the faster the memory operates. More information on the BIOS settings is provided further down this page.
However, note that the hardware required to cool an overclocked system properly is often crucial in the success or failure of the endeavour. Therefore, a user must do the necessary research before indulging in overclocking experiments.
Most RAM specifically designed to be overclocked usually has a heatspreader fitted to each module. This is a metal cover that covers the whole length of the module. Manufacturers of such RAM are: Crucial (its Ballistix memory), Corsair, (its XMS Xpert and TwinX memory), and OCZ (its EL Platinum memory).
Note that for modules that don't have heat spreaders it's possible to buy heatsinks for them. For example, the CoolerMaster RAM Chip Cooler.
To find information and vendor sites, enter the query in search engine; for general information just enter the search query ram heat spreaders.
A computer running a 32-bit version of Windows XP or Windows Vista (or any other 32-bit operating system) cannot make use of more than 3.2GB (gigabytes), which is about 3,276MB. A system running a 64-bit version of Windows XP/Vista can use a huge 128GB of RAM. Go to Page 1 of this article for more information on the memory limitations in Windows XP/Vista.
Note that if you're upgrading your RAM memory, a computer using Windows 95 or Windows 98 (first edition) won't recognise more than 256MB. Moreover, RAM that Windows can't cache (can't be recognised by the system) will be accessed as slowly as the virtual memory swap/paging file (win386.swp) that Windows creates on the boot hard disk drive to use when the amount of RAM runs out. Therefore, adding too much RAM can slow down a system considerably.
Unless you're using a non-Windows operating system such as Linux, and unless you employ the fix a link to which is provided below, your must have Windows 98SE (Second Edition), or run a later version, such as Windows 2000 or Windows XP in order to use more than 256MB of RAM.
Moreover, it has now become known the Windows 98 SE (Second Edition) has trouble with 512MB of RAM and more. Windows 95/98/Me systems were not designed to use large amounts or RAM. Most home users of Windows 95/98/Me are unlikely to require this much RAM in any case, so, if possible, it's advisable to install less than 512MB. If you need to use more, use Windows 2000, or Windows XP, both of which are based on the Windows NT architecture. Windows 95, 98, and Me are based on Windows 95 architecture.
If you have more than 512MB of RAM installed and this causes any problems, you can restrict the amount of RAM used to 512MB (or any other amount) by entering msconfig in the Start => Run box, clicking the Advanced button, and enter the appropriate restriction in the Limit memory to... box - and enable it with a check mark.
There is a configuration file fix that can be applied to make Windows 98 function with as much RAM as you are likely to throw at it. See this excellent article:
Windows 98 & Windows Me Memory Management -
You can read more about this by accessing a Microsoft Knowledge Base (KB) article 253912 called:
"Out of Memory" Error Messages with Large Amounts of RAM Installed -
Windows XP Memory Tweak Guide -
Windows Vista Memory Tweak Guide -
Note that information on tweaking memory in Windows Vista can be used with the versions of Windows 7.
Windows Vista: SuperFetch and External Memory Devices -
"Windows Vista sports a new memory performance enhancement system called SuperFetch and a new way to extend the virtual memory by way of External Memory Devices (EMD)." -
A desktop PC's motherboard manual should provide you with any jumper settings that are used to set the RAM's speed on comparatively old motherboards - for 66MHz EDO RAM, PC 100 SDRAM at 100MHz, PC 133 SDRAM at 133MHz, DDR, DDR2, DDR3 RAM, etc. - and the BIOS settings used for more recent motherboards that set the speed instead of motherboard jumpers - as well as set other optional settings such as the bank interleave and the timing settings.
Click here! to go to images of and information on the jumpers and DIP switches used on older motherboards to enable various functions (on this website).
Unfortunately, the ability of Windows to use RAM does not always coincide with ability of a motherboard's chipset to cache RAM, so be sure to check your motherboard's manual before you upgrade. The motherboard's chipset determines how much RAM can be cached. If a PC's motherboard can only cache a certain amount of memory and you install more memory than it can cache, it will slow the system down significantly, because the excess RAM will be accessed in the same relatively slow manner as the virtual memory swap file that Windows sets up on the hard disk drive to manage memory usage.
The moral of the story - if you have an ageing PC, always find out how much RAM your motherboard can cache before upgrading.
If you're buying RAM as an upgrade, purchase it from a supplier of quality RAM such as Crucial.
RAM of poor quality isn't worth any savings you can make, because it can be the source of all kinds of system failures.
Motherboards that use EDO RAM supplied as SIMM modules are no longer being made, but you can still purchase EDO RAM from suppliers such as Crucial, or second-hand from computer auction sites.
Overclocking means setting one or more of a computer's components to run faster than the manufacturer's recommended official setting(s). A practice that should be fully researched before it is indulged in, because applying settings that are too high for a particular device can make the system unstable and prone to errors, or even damage or render it useless.
If you increase the FSB speed of the motherboard - via the BIOS or, in older computers, by setting jumpers on the motherboard - you will overclock the processor, the RAM, the video card, sound card, and the disk drives.
Of those components, only the processor is likely to find the increased FSB unacceptable, because it is the component that is overclocked the most if the FSB is changed from an official speed of say 166MHz to an overclocked speed of 200MHz.
Doing this can result in a significant gain in performance if the processor can operate completely normally at the the increased FSB setting. But if the stability of the processor is made erratic as a result, you won't usually be able to overclock the RAM.
For example, suppose that the processor is an Athlon XP 2800+ with a Barton core that is designed to run at 2.08GHz on a 166MHz FSB. If the motherboard supports both DDR333 and DDR400 RAM, and has DDR333 RAM installed, you could try increasing the FSB to 200MHz, which the motherboard supports because the DDR400 RAM it supports runs on a 200MHz FSB.
Doing this would overclock the DDR333 RAM to run at the speed (really the frequency) of DDR400 RAM. Most DDR333 modules made by a manufacturer of quality, such as Crucial, can be successfully overclocked to the higher speed of DDR400 RAM. But increasing the FSB would also overclock the processor to run at 2.5GHz. A twenty-five percent increase over 2GHz!
If the system runs with stability over a lengthy period, fine, you're in luck, but the chances are that the processor won't like the high speed it's running at, and you might have to decrease the FSB setting significantly (if the BIOS or the motherboard's jumpers allow a range of settings that are higher than the official setting) to make it run with stability.
The only other alternative would be to overclock the motherboard's memory bus while keeping the FSB constant so that the processor isn't being overclocked at all. But motherboards that support separate bus settings for the memory and FSB are rare. In any case, using this method of overclocking the RAM only results in a minimal gain in system performance of around 5% at most. The best gains are always achieved by increasing the FSB so that it overclocks both the RAM and the processor.
Personally, I think that the results obtained by overclocking are mostly in the mind, and, since it stresses the components beyond the tolerances they were tested for, I don't ever bother with overclocking. If you want the fastest available system, unfortunately, as usual, you have to be prepared to pay the high prices for all of the fastest, latest components.
But if you want to attempt overclocking the RAM on your system, you can use the free MemTest utility, which runs from a floppy disk (independently of the operating system), and which stresses the RAM running at a particular FSB speed in order to determine its reliability at that speed. It can be used to find out how far the RAM can be overclocked.
Overclocking DDR Memory: Truths and Misconceptions - A Buyers Guide -
System Builder Marathon (Overclocking) Day 1 -
Overclocking Marathon Day 2 - A Home Brew -
Flash memory, sometimes called Flash RAM, was invented by Intel. It is now very fast when reading data or having data written to it, but unlike RAM memory, which loses its data when its source of power is switched off, it retains the data when the power is switched off, or the flash-memory device is removed from a system.
Devices that employ flash memory and which use the USB interface are called by several names - USB flash drives, USB keys, USB memory sticks, USB sticks, flash drive, jump drives, key drives, pen drives, thumb drives, etc. The latest flash drives use the latest USB 3.0 standard. Note that your computer has to provide USB 3.0 ports, or they have to be added to both a desktop or laptop PC via a PCI or PCI Express adapter card.
Nine USB 3.0 Flash Drives For Road Warriors [May 2011] -
"The best ultra-portable USB 3.0 storage products from 16 to 128 GB square off in a grand comparison. We found wildly disparate transfer rates ranging from 200 MB/s down to a snail's pace. At the end, though, two products rose to the top of our list." -
All memory cards, such as CompactFlash and SD, use flash memory. Flash memory is also used in solid-state drives (SSD) that can be used in desktop and laptop computers instead of conventional hard disk drives. An SSD drive uses much less power than a conventional hard drive, and it can withstand shocks (when a laptop is dropped, etc.), better than conventional hard drives. At the time of writing (May, 2008), the capacities of SSD drives have reached 128GB, although only 32GB SSD drives are currently in a price range that makes them a viable alternative to hard disk drives.
Sony's name for its pen drives is Micro Vault. Sony's site at sony.com has information on them that you can find by conducting a search of the site.
It is also capable of storing much more data than its advertised capacity, because it has inbuilt on-the-fly compression and decompression routines. Sony claims that this boosts the data storage capacity by up to three times. The drive is very small - a quarter of a centimetre thin, and roughly three by one-and-a-half centimetres in length and width.
It is also possible to buy a flash drive that is waterproof and has the cap attached to the drive so that it can't be lost. Integral makes waterproof flash drives.
To read the reviews of USB Flash Drives go to this page -
Microsoft provides a free program called Flash Drive Manager that makes working with several flash drives easy. You can even use it to set up a wireless network quickly and easily.
Each computer that you want to connect to a wireless network has to be configured manually with the required settings, but you can simplify the process by using the Flash Drive Manager to copy the settings from one computer to another.
The Flash Drive Manager isn't provided by Windows XP/Vista and Windows 7, but it can be downloaded from this page on the Microsoft website that also provides information on it:
Microsoft USB Flash Drive Manager (Standard) -
Visit the USB/FireWire Problems pages on this site if you are experiencing a problem with a flash drive. The most common problems are dealt with there.
I need to have several utilities/tools on a USB flash drive in order to be able to fix other people's computers, but I'm afraid that malware might transfer itself to the drive. If the drive has one, does a write-protect switch prevent malware from being written to it?
Not all flash drives provide one, but a write-protect switch or tab should prevent anything from being written to a flash drive. If the drive doesn't have a write-protect switch, there is a Windows Registry hack that should work on any flash drive. You will have to employ it on the computer that you are working on.
Registry Hack to Disable Writing to USB Drives -
Whichever method you use - a Registry hack or a hardware switch - verify that the write-protection is working by copying a test file to the flash drive. If the test write fails, then it is protected from malware.
At the start of the security screening at airports, etc., place your USB flash drive in the tray with your keys and coins. Bypassing the electronic screening devices will probably save the drive from being wiped by the powerful magnets that surround them.
You can use a generic USB driver for USB storage devices for Windows 98 that were written by a German programmer called Maximus Decim. It works with a wide range of USB storage devices. There is no home page and no support. To find download sites, you have to enter the man's name as the search query in a search engine. I found the following page that might not exist when you click on its link. If so, try entering the man's name in the Google search box at the top of this page (enable the Web Search option on the first search page).
Windows 98 USB Mass Storage Device Drivers -
Click here! to go to more information on this website on using USB 2.0 in Windows 98 and Windows Me.
USB thumb drives are inserted into a computer's USB ports, which are usually on the motherboard, but can also be on a PCI adapter card, some monitors, at the front of some computer cases, and even on some keyboards or monitors. But the most prevalent use of flash memory is in the form of cards that are inserted into devices such as cameras, MP3 players, notebook computers, PDAs, etc., which are read by a computer that doesn't use them itself via a memory-card reader.
USB flash drives - UFDs - can be used as fast, light, removable hard disk drives, and provide the possibility of creating alternative methods of booting a computer for use and for system-recovery purposes. Plugging in a UFD an alternative bootable drive allows for easy operating system deployment, system recovery, and the ability to run diagnostic and partitioning/formatting utilities that cannot be used easily or should not be run from the drive or partitions that they can work on.
If you want to use a USB flash drive with Windows 98 and Windows Me, you need to obtain the correct driver for that version of Windows from its manufacturer, which might not be easy to identify.
Using Windows Vista's ReadyBoost feature with USB 2.0 a flash drive can improve its performance.
"Windows ReadyBoost introduces a new concept in add-on system memory. You can use nonvolatile flash memory devices, such as universal serial bus (USB) flash drives, to improve performance without having to add memory "under the hood." The flash memory device serves as an additional memory cache — that is, memory that the computer can access much more quickly than it can access data on the hard disk drive."
ReadyBoost - http://en.wikipedia.org/wiki/ReadyBoost
Computers running Windows XP will only boot reliably from a USB flash drive that can be configured as a USB hard disk drive (USB-HDD). However, note well that many USB flash drives can only be configured as USB removable drives and will therefore not function as USB-HDD.
A flash drive that can be configured as a USB-HDD can also be difficult to identify. Many flash drives are generic devices that have been re-badged and different batches of drives can contain different components. If you want a bootable flash drive, the own-brand drives supplied by vendors should be avoided unless you know who the manufacturer is. When choosing a bootable drive, visit the manufacturer's website. If a particular model of flash drive is bootable, it will be mentioned as a feature. The manufacturer may also provide a utility that installs an operating system on the flash drive. The utility software may not be very good, but the fact that it exists indicates that the drive is designed to be bootable. Windows itself cannot yet boot from a USB flash drive, but there are tools that may enable you to use some Windows applications from a bootable flash drive.
You may need to use the following utility to make a flash drive bootable:
MKBT, Make Bootable - http://www.nu2.nu/mkbt/
Carry an entire operating system in your pocket -
"Running applications from a USB flash drive on a public computer is convenient but exposes you to malware and other limitations of the host PC. By installing a Windows-like version of Linux on a flash drive, you can take a complete operating system wherever you go and work in a safe, secure environment, even in an Internet café." -
If you have a flash drive that is bootable and your computer's BIOS allows booting from one, it is now possible to boot a full version of Windows XP from a USB flash drive.
An ideal way of recovering Windows XP would be if you could run a complete copy of it from a USB flash drive. The following free tutorial tells you how to do it. The webpage says that only Windows XP SP1 and SP2 are supported; there is no reference to SP3.
"WinUSB is a tutorial which allows the user to run a complete Windows XP version on an USB device/stick. This tutorial is some kind of manual which you have to follow, in order to let your modified Windows XP run on your USB device. Therefore you have to regard some requirements which are also important to the avoidance of any infringement of the copyright of Microsoft. You only have to click on the tutorial menu-button in order to read more..."
"Copyright advice: The following tutorial requires a valid licenced copy of Windows XP. Microsoft does not authorize the owners of Windows XP licences to run the licensed Windows version on more than one computer at a time. The registration of Windows XP also prevents running Windows XP on multiple systems. Due to that, you are allowed to use your licenced copy of Windows XP on only one computer. That does not prevent the use of WinUSB on another computer after shutting down the first system." -
Windows XP: booting direct from USB Options -
Carry a flash drive instead of a laptop -
Alternatively, it is possible to boot to a recovery system - a 'preinstalled environment', such as BartPE - from one. You can add all kinds utilities to it that are able to diagnose hardware problems and/or aid in the recovery of a system. The following articles tell you exactly how to do it, including how to format a bootable flash drive. Note that not all motherboard BIOS setup programs, especially the older ones, support booting from the USB interface. If the BIOS doesn't support it, then you can't use a USB drive of any kind to boot the system, but if it is supported, the option to enable such a system boot exists in the BIOS. However, even though the BIOS supports booting from a USB drive, there may be other incompatibilities that prevent it from being possible. The following two articles go into the details in depth.
Windows In Your Pocket -
[Windows] XP On Your Thumb Drive -
If you find the option to print the second Information Week article, you are provided with it on a single page that you can save to read instead of having to visit several pages.
It is also possible to boot some versions of Linux from a flash drive.
Use a USB Key to Install Windows 7—Even on a Netbook -
Creating Bootable Vista / Windows 7 USB Flash Drive -
If you require more information, try entering bootable usb flash drive as the search query in a search engine.
It is possible to run entire portable application programs from a flash drive. You can use them to work from any computer that has a USB port, save the files to your own application programs on the flash drive, and then save any documents you create to your main computer. At http://johnhaller.com/jh/ you can download portable flash-drive versions of many office and multimedia applications - email clients, browsers, Open Office, Winamp, FTP programs, HTML editors, Instant Message (IM) programs, and personal management calendars are available. With the new U3 standard - visit this page for information on it - http://www.everythingusb.com/u3.html - it is even easier to use a flash drive as a portable computer.
Carry a flash drive instead of a laptop -
"You can avoid lugging a laptop everywhere by installing your favorite apps on a USB flash drive and running them on any computer you want. I'll guide you in selecting a flash drive that's best suited for portable software and tell you which apps you should install..." -
Free software on USB enables portable computing -
It is now possible to run a full free office suite from a flash drive. You can download the Portable OpenOffice.org from openoffice.org. It contains a word-processor, spreadsheet, database, and drawing and presentation tools. Note that it is beta software that isn't yet the finished product.
Even the smaller of the high-speed USB flash drives (64MB, 128MB, 256MB), known by several names such as memory sticks, thumb and pen drives, have enough permanent flash memory to make them a viable on-site and off-site back-up option for data files. The greater the data capacity, the greater the cost. A 128GB drive is very expensive, but a 16GB drive can currently (July 2009) be purchased for under £20. The 128GB Kingston DataTraveler 200 currently costs US$546. (The 2.5" 500GB Western Digital Passport external hard drive is faster and has a very much higher data capacity costs only $99, so I am not sure who is going to be buying those extra-large capacity flash drives.) Flash drives last a long time if they are only used for storage like floppy disks, so the earliest drives are still in use. I still have a 64MB flash drive that has more than enough space for documents.
Storage capacities currently (time of writing is July 2009) range from 64MB to 128GB with size and price per capacity increasing and improving all the time. Some flash memory now allows approximately 1 million write or erase cycles and have a 10-year data retention at least.
The drives with the highest capacities now have enough flash memory to store an entire system made up of the operating system, the applications it runs, and the data files that the applications generate.
Flash drives are believed to work for up to 10,000 write/erase operations. However, some sources indicate that flash drives can survive for up to ten million operational or write/erase cycles.
Crucial, Corsair, Kingston, SanDisk and other memory manufacturers have brought out lines of inexpensive second generation USB 2.0 thumb drives that are smaller, faster, and weigh less than the previous generation. The pen drives are no wider than their USB 2.0 connector, which is accessed by removing the drive's cap. Take care not to lose the cap if there is nowhere on the drive to attach it.
Most SanDisk flash drives have retractable connectors instead of caps.
Visit the US crucial.com site or crucial.com/uk for the UK site to see examples of the flash drives that Crucial sells.
To lose data on burned CD/DVD disks only requires the disc to be damaged or scratched, and it is known that recorded discs have a limited shelf life that can be as low as two to five years for cheaper makes of disc.
However, flash drives are very durable, and the data stored in one will remain intact as long as the drive can be accessed, which is effectively for as long as there are computers that have USB 1.1 or USB 2.0 ports, because the drives can work on the earlier and slower USB 1.1 ports. It is known that the drives can survive and still be accessed after having gone through a full washing cycle in a domestic washing machine.
Scratches and dust can render the previous forms of portable storage such as CDs and floppy disks unusable, but this is not the case with flash drives. Because of their durable solid-state design, they often survive casual accidents - impacts, being dropped, being put through a washing machine, or even being dropped in a liquid. This makes them ideal for transporting files from one location to another, such as from home to school or the office. Almost universal USB support on modern computers allows the drives to be used in most places.
The data reading and writing rates vary from drive to drive, but they are fast. For example, Kingston's Data Traveler Elite has nearly a 20MB/s (20 megabytes per second) reading rate, and up to 12MB/s writing rate, and has integrated data protection by providing optional 128-bit DES hardware encryption. Corsair's flash drives have a reading rate of almost 20MB/s, a writing rate of 14MB/s. Moreover, the rubber cladding around them makes them waterproof and well suited for outdoor use.
A flash drives should have an LED light that indicates when data transfers are taking place, and have a write-protect switch that is enabled to prevent the drive from being written to in the same way as a floppy disk has a slider that prevents the disk being written to if it is manually moved into the position that leaves an open gap that the floppy disk drive reads and interprets as a write-protected disk. If a message comes up unexpectedly saying that your flash drive is read-only, then the switch has somehow been enabled. The switch is located on one of the long thin undersides of the drive. Note that not all flash drives come with a write-protect switch.
If your computer only has USB ports at the back of its case. If the back of the case is usually inaccessible, you can buy an inexpensive USB hub that connects to a USB port and allows you to plug in the flash drive without moving the case.
Alternatively, a basic USB extension cable is a very cheap solution at around £4/$7 each. I use extension cables with all of my USB devices even if the USB ports can be easily accessed. They reduce wear on the connections, and, if there are no USB ports at the front of the desktop PC's case, make crawling on the floor to connect the devices to the back of the PC case unnecessary.
Using a flash drive is very simple in a system running Windows XP, because it loads the device drivers automatically when you plug the drive into a USB port. After the drive is plugged in, the drive's LED light should light up and you'll hear Windows make a sound. A message should come up saying that Windows has detected new hardware and is loading the drivers. Then another message comes up telling you that the drivers have been installed. You can now copy files to the drive immediately, because the drive doesn't need to be formatted.
It is listed as a drive in My Computer in Windows XP and in Computer in Windows Vista and Windows 7. Just copy some files, locate the newly listed drive in My Computer/Computer, click on it to open its window, right-click in the right-hand window and paste the files. Or select the files you want to transfer to the drive, right-click on them with the mouse and choose the Send To option, which should list the drive as the destination.
If the drive already has files copied to it, when you plug the drive into a USB port, Windows XP/Vista/Windows 7 installs the drivers and brings up a window containing a list of the files, or the window appears that also presents itself when you insert a recorded CD/DVD. It provides a list of the options that you can choose to run. To view the files, all you have to do is click on the Open folder to view files option.
To save new or updated files to the drive just use the Save as option in your application program that you would normally use to save files to the hard drive, and select the drive letter or named drive that represents it from the drop-down menu. It is sometimes called a Removable Disk or an Unknown drive. The drive letter that the drive has been assigned should appear in Windows XP in My Computer (Computer in Windows Vista and Windows 7).
If you unplug the drive while the computer is running, Windows unloads the drivers. Before you unplug the drive, click on the new icon that Windows should have placed in the System Tray (Notification Area). It looks like a green tree growing out of a grey base in Windows XP. The icon in Windows Vista and Windows 7 are indescribable (just move the mouse cursor over the icons until the right one describes itself). To find it just pass the mouse pointer over the icons until a balloon comes up describing it. Click on Safely remove USB Mass Storage Device. Windows then displays this message: Safe to Remove Hardware.
Note well, don't use excessive force when plugging a flash drive into a port, because if its USB plug loosens or breaks, the device will be rendered useless. Likewise, take care when unplugging the drive. When a drive is plugged into a USB port at the back of a laptop computer, take care when lifting the computer, because if you lift the front up first you can bend the flash drive and render it useless.
Most USB flash drives use a mass-storage class of drivers that are provided by Windows Me, Windows 2000, Windows XP, Windows Vista and Windows 7. However, in order to operate under Windows 98 SE, a USB flash drive requires a driver that you might be able to obtain as a download from its manufacturer's website.
For the versions of Windows 95 with USB support the driver situation is dire. Drivers are almost completely unavailable, but you might be able to find a generic driver that works by using a search engine to perform a web search.
Crucial no longer provides security software with its flash drives because of having to devote too much time to support issues. There are many flash drives that come with encryption software, but you usually have to pay extra for them. However, there's no need to worry if a flash drive you've purchased doesn't come with it. If you want to keep the data on a flash drive secure, you can make use of a third-party encryption utility, many of which are free. If the data on the flash drive is scrambled to a high degree it's secure because only expert hackers could crack the encryption, which none of them would bother to do.
TrueCrypt from truecrypt.org is a free open-source application ("Free open-source disk encryption software for Windows 7/Vista/XP, Mac OS X, and Linux") that can create encrypted drive volumes on any kind of removable storage. The encrypted drives are password-protected and appear in Windows Explorer, which means that they can be used in the same way as any normal drive. For example, using TrueCrypt, you could create, say, a 250MB encrypted drive on a flash drive. Everything you copy to the drive would be encrypted.
There are utilities, such as WinZip, that can compress and encrypt files by using up to 256-bit AES encryption so that they take up about half or less of their uncompressed space, making them secure from everyone who isn't an expert hacker. WinZip isn't free, but there are many free standard encryption tools, most of which don't provide compression, that are nevertheless very easy to use.
You can try using the search query free file folder encrypt in a search engine to find links to free encryption tools.
Software protection is not as good as hardware protection. You can now purchase a self-locking USB stick with a built-in numeric keypad. Visit the following link to read a review of the device.
Review: Corsair 2GB Flash Padlock USB Stick -
Kanguru's Secure USB Memory Stick : USB Flash Drives: A Threat For Companies? -
Crucial Gizmo hi-speed USB flash drives allow the drive to be divided into public and private areas by using Secure-D Software.
"The Secure-D software is an application that allows you to password-protect secure files on your USB drive. Secure-D allows you to divide your USB drive into two different areas. The public area, which comes up automatically when you insert the USB drive into a USB port on the computer, is accessible by anyone using your drive. The secure area is password-protected and no one can open, copy, or write files to it without entering the password first. CAUTION: When you use the Secure-D software to create or change the size of the public and secure areas on your USB drive, all of the information on the drive is overwritten. If you plan to use both public and secure areas on your USB drive, you need to install Secure-D and create the areas before you save information on your drive. If you've already saved information on your USB drive and you want to create areas, save the existing contents elsewhere before you create the areas, and then copy the information back onto the drive afterward."
Magneto-resistive RAM (MRAM) is not available yet. It is said to be a thousand times faster than the DRAM (dynamic RAM) used in computers, and, like flash memory, it retains its data when not powered.
In the near future, Flash RAM of this kind will probably be incorporated into the processor and render HDDs redundant. The operating system will be able to shut down and start up immediately from where it left off.
Visit http://en.wikipedia.org/wiki/Memory_card for information on memory cards.
Memory cards are constantly becoming smaller in size, larger in capacity, and cheaper. They are ideal for storing digital photos, for use with Personal Digital Assistants (PDAs), particular MP3 players, and digital video cameras.
If you use several different kinds of devices that use their own kinds of memory cards, you can purchase memory-card readers that can read the different cards.
For instance, an MP3 player uses MMC cards, a PDA uses CompactFlash cards, and a Sony Vaio notebook computer uses it own Memory Stick cards.
The CompactFlash Association has recently announced that the successor to CompactFlash are to be known as XQD memory cards. When SDXC and SDHC memory cards replaced the old SD cards, they retained the same size and shape, but XQD cards use a completely new design and the cards themselves look more like an SD card than CompactFlash cards. According to the CompactFlash Association, using the PCI Express graphics standard instead of the ageing PCMCIA interface (used for latop adapter cards until it was replaced by ExpressCard), the new interface makes the cards significantly faster than CompactFlash and SD cards. The final specification for the XQD standard was announced in December 2011 and Sony has already made 16GB and 32GB XQD cards available, so it's just a matter of time until the other camera manufacturers jump on board.
Secure Digital (SD) cards with built-in Wi-Fi connectivity have been available for several years, but only now in early 2012 is there an official standard for this type of connectivity. It is called the Wireless LAN SD Standard and provides 802.11n connectivity to both full-size SD/SDHC/SDXC and Micro SD/SDHC/SDXC cards. The SD Association is the body responsible for the standards used by SD memory cards, but it is late in delivering a standard because Eye-Fi, a Californian company founded in 2005, has been marketing SD cards with integrated Wi-Fi connectivity for several years. That said, the official standard will now be making development of wireless SD cards easier for other manufacturers. The standard allows devices that are built around it to be fully interoperable, allow images and video to be transferred wirelessly to both desktop and laptop PCs and Internet services and makes possible peer-to-peer transfer capabilities between cameras, smartphones and tablet computers. The standard also allows a device equipped with a Wireless LAN SD card to act as a control point for other devices, such as a TV.
You could spend a long time transferring files from the devices to a desktop computer by using, say, USB cables. But if you buy an inexpensive memory-card reader, you can eliminate the need to plug and unplug lots of different USB cables.
Most memory card readers are inexpensive devices priced at around £30 or less. There are several types that can be used with a PC by using an internal or external USB connection.
The 6-in-1 Media Reader requires a 3.5" drive bay of the kind that houses a floppy disk drive. It reads Multimedia Cards (MMC), Secure Digital (SD), Memory Stick, PC Card (PCMCIA), CompactFlash, and SmartMedia card formats. You can copy the contents of one type of card to the desktop computer's hard drive, insert a different card, and copy the contents to it, or you can just copy the contents to the hard drive.
The USB 2.0 6-in-1 Flash Reader, is an external USB device that can be connected to either a notebook or desktop computer. It also has a USB 1.1 port that enables you to connect a printer or scanner to it.
CompactFlash.org - http://compactflash.org/
CompactFlash FAQs - http://www.compactflash.org/faqs/faq.htm
Memory Cards, Part 1: CompactFlash From 8GB To 64GB -
"Professionals rely on high-speed CompactFlash cards. Today we're looking at a handful of different options from Lexar, Samsung, SanDisk, Silicon Power, and Transcend with capacities up to 64GB and speeds up to 600x (as high as 90 MB/s)." -
Roundup: CompactFlash Cards For Professionals : Compact Flash Powerhouses Reviewed -
13 SDHC Memory Cards Reviewed : SD Memory Cards for Professionals -
Some photo printers have the capacity to read data directly from the memory cards used by digital cameras. Such printers usually offer advanced layout and quality options, and can also be used as a memory card reader when connected to a computer. Just make sure that a photo printer with such a facility supports the same memory card format as your digital camera.
Installing an external USB memory card reader is a very simple matter. You merely have to install the device drivers that should be provided on a CD that came as part of the package, and plug the reader via a USB cable in to a USB port.
An internal memory card reader is relatively simple to install in a 3.5" bay of a PC case in which a floppy disk drive (FDD) is usually installed. Card readers that have an inbuilt FDD are available, so, if you need to have one, you can replace the existing FDD with the combo device.
An internal memory card reader must have a USB header on the PC's motherboard. The information about the location and and order of the pins on the header are illustrated and explained in the PC's motherboard manual, a copy of which can be downloaded from its manufacturer's site. If you need to identify the motherboard in a PC, the free CPU-Z utility is ideal. You can then locate the manufacturer's site by using a search engine.
USB headers on a motherboard have nine pins, but memory card readers only use four of them. If any other device is using one row of pins, you can install the reader on the second row.
Instructions on how to install the memory card reader should have come with the device. It will tell you if you have to install the device drivers before installing it or after installing it. Windows XP and Windows Vista and Windows 7 should detect and install the drivers automatically when the PC is started after the device is installed. The manufacturer's drivers are required if you are installing the card reader in a Windows 98 or Windows Me system.
In any case, it is a good idea to install the manufacturer's drivers, because they provide information in My Computer/Computer (Computer in Windows Vista and Windows 7) that explains which drive letter relates to which card format. That is useful if the reader supports several types of cards.
How the card reader is installed in the PC case depends on the type of case. Some cases come with rails (runners) that you screw to the drive. When you push the drive through the open 3.5" drive bay, it clips in. To remove the drive, you just have to release the clips in the front of the drive and slide it out. See the image below of runners fitted to the side of a CD drive. You can see the clips on the end clearly in the runners in the foreground of the image.
Other cases have fixed drive bays; you insert the drive so that it is flush with the fascia of the case and screw it to the bay with four screws. If you are replacing a floppy disk drive (FDD) with a combo card reader/FDD, you can install it in the same bay. But, you'll probably have to remove the face plate of the spare 3.5" bay that most cases have if you are installing just a card reader and want to keep the existing FDD.
The physical installation is done in the same way as installing a FDD except that the reader is connected to a USB header on the motherboard instead of a dedicated FDD connector on the motherboard. Click here! to go to the page on this site that deals with installing a FDD. It provides information on troubleshooting if the FDD doesn't work.
You have to know how to install a FDD if you are installing a combo device. You must attach the cable(s) to the drive before you install the drive so that you can feed the cable(s) into the bay before the drive itself is inserted. It is usually very difficult to attach the cable(s) after the drive is installed.
After a memory card reader has been installed successfully, several new drive letters should appear in My Computer/Computer - usually one drive icon for each of the different card slots that the reader has. The card reader will also appear in the Device Manager. To see it in Windows XP and Windows Vista, enter the command devmgmt.msc in the Start => Run box (XP) and the Start => Start Search box (Vista) Click the + beside Universal Serial Bus controllers. In Windows 7, just enter device manager in the Start => Search programs and files box to be presented with a clickable link to it.
If the internal card reader doesn't appear in Windows, make sure that you connected the USB header properly - that you used the correct header on the motherboard and that the cable is plugged in the right way around.
The following article provides an image of the installation on a USB header on the motherboard.
How to Install an Internal Card Reader -
If an external memory card reader doesn't appear in Windows, you can verify if the external USB port is working by attaching a USB mouse to it. You can unplug and plug in USB devices while the PC is running, because USB and FireWire devices support such 'hotplugging'. If the mouse works, the card reader's drivers have probably not been installed correctly and should be reinstalled.
The internal card reader doesn't require a power cable to be attached to it from the PC's power supply because internal USB devices are powered via the USB cable. But, if you have a combo unit, and its FDD doesn't work, then make sure that a FDD power cable from the power supply is connected to the drive's power connector. If the FDD's light stays on all the time, its data cable is the wrong way round. The wrong end of the cable is attached to the drive.
If you want to know about the technical details of how RAM works, visit this article. -
How Computer Memory Works -
And if you want to know how Windows, and other operating systems, make use of a virtual memory swap file on a hard disk drive to expand the system's RAM, read the following article. -
How Virtual Memory Works - http://computer.howstuffworks.com/virtual-memory.htm
How Flash Memory Works - http://computer.howstuffworks.com/flash-memory.htm
"Windows 98 & WinME Memory Management" - http://aumha.org/articles.htm - includes information on RAM and the Windows Virtual Memory swap file.
To conduct your own search of the web for additional information on RAM or flash memory, or specific products mentioned on this page, you can make use of the search engine of your choice.