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Operating Systems

No easy way to diagnose a bad memory module

Why is it so difficult to determine whether Windows errors are because of faulty system memory?

The other day, my friend Howard asked me about an error message that appeared whenever he tried to open Internet Explorer on his aging Windows XP machine. After a little basic long-distance troubleshooting (Howard lives on the other side of the country), we determined that it wasn't a problem with his network connection.

Howard isn't very tech-savvy, unfortunately. (He's a handicapping wiz, though, which explains why he needed to get back online--he had a longshot lined up at Gulfstream.) My brother Larry, who lives in the same town as Howard, restored his Web access by logging him into another user account on the PC. But that didn't fix the original problem.

I suspected it was because of a bad memory module. Normally, I would recommend downloading the free, open-source MemTest86+ memory-testing utility to a floppy disk or CD and then booting from that disk or CD to test the machine's memory modules. (MemTest86+ is actually donationware, so if you find it useful, consider tossing a couple of ducats into the virtual hat.)

Memory-testing utilities are a challenge to use
This would be a relatively easy procedure for anyone with more-than-average PC experience, but it takes a little more technical background than Howard possesses. The first problem is talking Howard through the process of downloading the program to a removable, bootable medium. A floppy we might manage, but I doubt Howard has ever burned a CD.

Next is ensuring that his PC's BIOS is set to allow booting from either a floppy or a CD. I could probably talk Howard through the process of entering his PC Setup program, but having him navigate and alter its settings is too perilous for me. The chances of rendering his PC unusable are too great.

Even if we got the program onto a floppy or CD and managed to boot the machine from the disk, Howard would have to run the memory-testing utility and make sense of the results. MemTest86+ is not known for its crystal-clear interface, and the program's documentation is nearly nonexistent.

There are some alternative memory-testing utilities. DocMemory from is similar to MemTest86+: it's free (at least for a limited time), it runs off a floppy, and it's a challenge to use, though it's better documented than MemTest86+.

Another option is Microsoft's Windows Memory Diagnostic, which is offered through the company's Online Crash Analysis site. Windows Memory Diagnostic works much like the other two memory testers, but its tests are more basic. The program is well documented, and its test results are easy to find.

Skip the testing and just swap out the modules?
Ultimately, it would be simpler and less time-consuming for Howard to open his PC's case, remove the existing memory modules one at a time, and restart the machine to determine whether the problem recurs. If it doesn't, he can take the bad module he just removed to his local electronics store and buy a new one of the same type--though maybe with a larger storage capacity.

If Howard's PC has only one memory module, he can simply try placing it in another memory slot on his system board just in case the problem is the slot rather than the module itself. If changing the slot doesn't solve the problem, Howard can buy a new module of the same type, put the new stick in the memory slot, restart the machine, and see if that works.

If the new module doesn't change anything, Howard will have to make another trip to the store to return it. He'll be back at square one, though he'll know memory modules aren't the source of the glitch. What really bugs me about the situation is how difficult it is to determine whether your PC's memory has gone bad. Why can't our systems diagnose themselves and help us fix them? OK, I'm dreaming, I know. But some day....

Some memory-troubleshooting helpers
A great resource for diagnosing your PC's memory woes is on the PCStats site. The Microsoft Developer Network offers a comprehensive description of system error codes. And one of my favorite diagnostic utilities is the free Error Messages for Windows by Gregory Braun.

I'll continue the saga of Howard's error-code-generating PC in a future post--if I can ever get him off the handicapping pages.