Few people realize it, but purchasing the best RAM for your system and needs is half the battle where RAM upgrades are concerned. Adding the stuff to your computer is easy, but finding reliable sticks of RAM that play well together can be a real challenge. Doing a lot of research before placing an order or listening to what the employee at the computer store tells you can save considerable hassle down the line, so grab the documentation that came with your computer and prepare to learn your motherboard inside and out.

The motherboard is the large wafer of silicon that the CPU, video card, hard drive, RAM, and other components all connect to; it determines what memory is compatible with your system. The first thing you need to know is the best type of RAM the system can handle, as many motherboards are compatible with multiple types of RAM. Older computers use SIMMs (single in-line memory modules) that must be installed in pairs in the same memory bank (or paired set of memory slots).

Newer PCs use DIMMs (dual in-line memory modules) that you can install singly, although some DualDDR (also called dual-channel DDR) motherboards perform better when RAM is installed in paired sets. If your motherboard supports this feature, use it. For example, instead of purchasing a single 1GB stick of RAM, purchase two 512MB sticks and install them as a pair. If you opt for this latter option, do yourself a favor and purchase a matched pair of identical sticks of RAM from the same manufacturer (some companies sell pre-paired kits). Lots of companies make decent RAM, but computer enthusiasts looking for matched pairs typically choose higher-end products from companies such as Corsair (www.corsairmicro.com), Crucial (www.crucial.com), GeIL (www.geilusa.com), Kingston (www.kingston.com), Mushkin (www.mushkin.com), and OCZ (www.ocztechnology.com).

All of these companies have Web configuration guides and sales specialists that will help you determine what type of memory is compatible with your motherboard and what memory speeds will provide the best performance within your budget. Memory sticks have clock speeds measured in megahertz just like CPUs do, and they also have latency speeds, data bus rates, voltage requirements, and other considerations that can make a shopper's head spin. Research what is right for your motherboard and go with the company that is most helpful and also has reasonable prices.

Some people say you can never have enough RAM, and although we agree in spirit, the operating system and motherboard you use actually dictate the maximum amount of RAM your computer can address. Even older versions of Windows (Windows 95/98/98SE/Me) can address up to 2GB of RAM, but a glitch sometimes prevents them from taking advantage of all that memory. Microsoft has posted a workaround at support.microsoft.com in Knowledge Base Article 253912, "Out of Memory Error Messages With Large Amounts of RAM Installed." Windows XP and Windows 2000 users can address even more memory than that (although typical home users would never need to), so the main limiting factor in the amount of memory you can add is your motherboard. Check its specifications closely to make sure you don't buy more RAM than it can handle.

Step 1: You're Grounded

Prepping the area around the computer and handling RAM properly is important if you want to avoid expensive damage. Get all liquids out of the area where you'll be working and head to the local computer or electronics shop to see if it has a grounding kit that will dissipate static electricity from your body into the ground where it belongs. Static electricity is the bane of RAM; one zap can fry the fragile chips in an instant, so stay away from carpet if you can and at the very least touch a grounded metal object to discharge static before handling any RAM. If your computer is plugged into a wall socket, then all parts of its internal metal frame are grounded, but try to discharge static electricity into another grounded metal object that is nearby in case the wall socket itself is not grounded.

If you are sure that the wall socket your PC is using is grounded, you may want to keep the computer plugged in during the entire installation procedure to make sure any static electricity that is generated during the process is safely absorbed. Some people prefer to unplug the computer because there's always a possibility of an electrical short, which could be harmful to both you and the computer, so the choice is yours.

If you really want to be cautious, buy an antistatic wrist strap, which consists of a grounded wire attached to a wrist strap that you can wear to shed static electricity continually throughout the installation process. If you're working in a carpeted room, a grounding strap is especially prudent, and they are available for less than $10.

Step 2: Crack The Case

Every computer manufacturer seems to use a different case design, and you'll need to look at the documentation that came with your computer to see how to open the thing up. You need unfettered access to the motherboard, whether that means removing a panel, popping some stays to split the case in half, or performing some other magic. Open the case in an area where there is plenty of lighting because RAM slots are typically difficult to see and access, and don't drop the computer if you have to move it because hard drives and optical drives are especially susceptible to shock damage.

Step 3: Clear A Path

Once the case is open, you may need to move some internal cables around to clear a straight path to the RAM slots. Move cables or bundles of cables one at a time, paying attention to where they are connected within the computer so you can reseat them later if necessary. You may need to detach some of the cables to access your motherboard's RAM slots; if this is the case, check the ends of the cables for release latches before applying any force. Grab cables by their plastic terminators to detach them instead of pulling directly on the cables themselves and don't lose track of what sockets the cables attach to so you can properly reseat everything later.

Examine the RAM slots carefully to make sure they aren't clogged with dirt, fuzz, or other gunk before you insert the RAM chips. If you find that they're plugged up, don't clean them with a cotton swab or with any liquid. Cotton is notorious for pulling apart when it comes into contact with the irregular surface of the RAM slot and can make the problem worse, and water or other fluids can damage the slots or at least set them up for future failure due to corrosion problems. Even fabric, paper towels, and facial tissue leave particles behind that can interfere with the RAM, so if cleaning is necessary, use a can of compressed air to blast the slots clean.

Step 4: Open The Hatch

Now that the RAM slots are accessible, you can remove existing memory sticks if necessary or prepare the slots for the placement of the new memory sticks. Older computers that use 72-pin SIMM chips have slots with fragile clips on either end that you'll have to open before removing or inserting a SIMM. Remember that SIMMs must be added in pairs and that each pair must be located in the same memory bank. Refer to the documentation that came with your computer to figure out the configuration of your motherboard's memory banks and prepare the appropriate slots.

DIMMs are much easier to install. Just press down on the handles on either end of a DIMM slot to open it, which gently ejects existing RAM and prepares empty slots for the installation of new sticks.

Step 5: Secure New Memory Module(s)

The moment of truth has arrived—it's time to install the RAM module (or modules). Check the documentation that came with your PC closely to see if you need to fill the slots in any particular order. (This is especially important for systems that use SIMMs, as you must completely fill their memory banks before they can detect any RAM.)

Pick up your memory module by its top or side edges, but avoid touching any metal contacts at the bottom of the stick. Oil from your fingers can interact with the metal and eventually cause corrosion. Some memory sticks are bare silicon wafers with black RAM modules embedded on them, but most high-end RAM comes with metal heat spreaders attached to either side that dissipate heat. Don't worry about touching the heat spreaders, but be careful not to accidentally pull them off.

For SIMMs, make sure the clips are open, insert the RAM at a slight angle relative to the slot, make sure it isn't in backward (holes in the bottom of the chip should match up with pegs in the RAM slot), and gently swing it straight up into place. You'll know it's secure when the clips on either end of the slot click and hold the RAM in place.

With DIMMs, make sure any clips you opened in the previous step are still completely open and push the RAM straight down into the memory slot, placing a thumb on either end of the top of the RAM stick so as to apply pressure as evenly as possible. Don't use too much pressure or you may crack the motherboard beneath the RAM slot, and avoid "sawing" the RAM into place (by rocking it back and forth) to avoid damaging the metal contacts. If it feels like a reasonable amount of force isn't getting the job done, then the most likely cause is that the RAM is not seated correctly in the slot. Lift it back up, reseat it, and try again. There's also a chance that you're installing it backward, so make sure that notches cut into the bottom of the RAM stick match up with plastic posts present in the RAM slot.

The clips on either end of the DIMM slot should swing up and snap into place automatically once the RAM is in position. You may have to manually secure the clips on either end while simultaneously maintaining pressure on the top of the RAM module with your free thumb. Just gently pull upward on each clip until it locks into place. (The clips should nestle into notches cut into either side of the RAM module.)

Repeat the above steps for any other RAM sticks you are installing, paying close attention to memory banks and avoiding scraping the RAM together or accidentally dropping it into the space between two slots.

Step 6: Testing One, Two, Three

Don't put the cover back on the computer just yet. Reconnect any cables you may have had to detach during installation, plug the computer back in if necessary, and look in the computer's users manual to find out how to access the BIOS (Basic Input/Output System). This usually entails pressing F2 or F8 during the boot process, but the procedure varies among manufacturers. Some BIOSes let users navigate via a mouse, but most require keyboard input. Use the arrow keys to highlight menu entries and the ENTER key to select entries.

Changing BIOS settings accidentally can be a detriment to the health of your PC, so try not to make any adjustments when you boot into the BIOS interface. You're just there to see if the BIOS recognizes the RAM you just installed and reports the proper memory capacity, so find the steps in the documentation to accomplish that, exit the BIOS, and reboot the computer. If the BIOS doesn't see the new RAM, the memory is either incompatible with your hardware or is damaged, so exchange it if possible.

Step 7: Working With Windows

Once the RAM checks out in the BIOS, reboot the computer and make sure Windows recognizes the new memory. Right-click My Computer (WinXP users may have to click Start and right-click My Computer), click Properties, and look for the RAM figure in the General tab of the resulting dialog box. It should match up with the amount of memory you installed.

Step 8: Case Closed

Once everything checks out, you should close the computer's case to cut down on the amount of time its innards are exposed to the elements. Dust, pet hair, and other particles may build up quickly because of the multiple fans inside the computer's case, so give the inside of the case a thorough blasting with compressed air before sealing things up.

When closing the case, be careful not to pinch cables between the case and the computer's frame. It is especially important to make sure no internal cables are sticking out of the side of the frame when you close the case because pinching or severing one of those cables can cause a short in the computer's power supply. Also keep mouse, keyboard, and other cables pulled well out of the way when closing the case.

Step 9: Burn It In

If your memory passed the previous tests, there's a good chance it will last for years. To be on the safe side, however, you should give it an intense workout for several hours to make sure it doesn't overheat and fail when stressed. Keep as many programs open simultaneously as possible for as long as possible, watching for memory errors. Another great way to stress-test memory is to spend some time playing hardware-intensive 3D games, such as idSoftware's Doom 3.

Did It Work?

You system should run more smoothly with more RAM installed, but if you need quantifiable evidence, download some free benchmarking software, such as Futuremark's PCMark or 3DMark (www.futuremark.com) before installing the new RAM and record the performance of your initial configuration. Then run the benchmark software again after you install the new RAM (multiple benchmarking sessions in a row also are a great way to stress-test RAM), and you'll get a nice, neat, numerical report proving the additional RAM is making a difference.

by Tracy Baker