Troubleshooting: Identify failing RAM chips

What if my PC won't boot?
All is not lost if you can't get your PC to boot up after installing your new RAM. Try these steps to resuscitate your computer:

  1. Shut down your PC, unplug it, and open the case.

  2. Check your RAM modules to make certain they're properly seated. You may need to remove and then reinstall them.

  3. Check for other loose cables, boards, and so on. Reseat them if needed.

  4. Restore the power to your PC and try booting up again.

If your system still doesn't boot up properly, try this:
  1. Pull the plug, remove the new RAM, and see if your computer boots. If you removed working RAM to install the new RAM, put the old RAM back in again.

  2. Did your PC boot with the previously working chips? If so, then return the new chips to the manufacturer for replacement. If not, you may need to take your PC to a repair shop for additional service.

What if my PC beeps when I turn it on after installing RAM?
Most PCs will beep once when starting up just to let you know that everything is OK. If you hear more than one beep or one unusually long beep when you reboot, you have a problem. Keep in mind that not all PCs use the same BIOS chips. The type of BIOS used in your machine will determine the sequence of the beeps (known as beep codes). Check your PC or motherboard manual so that you can determine what problem the beeps identify.

What if some of my RAM is good and some is bad?
If you receive an error message that says RAM Bad, how do you figure out which chips are good and which aren't? If you don't have a chip tester (and most of us don't), then try this method to test each chip:
  1. Shut down your PC, unplug it, and open the case.

  2. Take a look at your RAM sockets. If you have any empty ones, try swapping your RAM modules into them.

  3. If you don't have any empty sockets, swap the RAM module in the first bank with the RAM module in the second bank.

  4. Plug in the power and restart your PC.

  5. If the error message returns, shut down your PC and unplug it again.

  6. Try eliminating the modules one by one to isolate the bad chip. Note: This may not work if your system requires you to have RAM modules installed in pairs. If so, remove the chips in pairs.

RAM myths and facts
Gold vs. tin: Motherboard memory sockets and RAM modules use either tin- or gold-plated connectors. Some people suggest that mixing gold with tin leads results in oxidation and eventually corrodes the leads, resulting in memory errors. While strictly true, the chemical process is so slow that you'd have to leave the memory installed for years to see any changes.

How much RAM is too much? That's a tough question. Some say you can never have too much RAM. But before you go hog wild, know thy motherboard. Find out what chipset it uses and how much RAM it can comfortably accommodate. In some cases (mostly with older systems using a Pentium II or older CPU), adding too much memory can actually slow down your computer. The key factors here are the level 2 (L2) cache and the supporting chipset built into the motherboard. The L2 cache is a chunk of high-speed memory (typically 512K) devoted to the CPU that holds recently used data. When the CPU needs that data, instead of going to slower system RAM, it first checks the speedier cache. Most modern systems can easily cache up to 512MB of RAM and then some.


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