Tech Line

Fixing Forgetful Computers

Isolating and solving memory errors is a snap with the Windows Memory Diagnostic tool.

• By Chris Wolf
• 09/25/2007

I feel your pain, Todd. It’s often tempting to purchase cheap memory but, ultimately, you get what you pay for. Some discount memory vendors back up their products with lifetime warrantees, but that’s only meaningful if the vendor actually backs the warranty. That’s a lesson that I once had to learn the hard way. You may pay a little extra for Crucial or Kingston memory, but you’re also buying peace of mind.

Since you have already solved the problem using the tried-and-true “replace a bad part with a known good part” approach, let’s look at how to prove the problem is indeed faulty RAM. Lucky for us, computers have yet to respond to our requests like politicians. Instead of saying "I have no recollection...," they simply provide us with a Stop error that is typically accompanied by the notorious blue screen of death. Windows usually generates the following Stop error codes in response to a physical memory failure:

• 0x0000000A
• 0x00000050
• 0x0000008e
• 0x000000D1

Now while the error code is a good start, you’re probably going to want more specific proof of the faulty stick of RAM. To get the proof, I recommend that you use the Windows Memory Diagnostic tool. Windows Memory Diagnostic can run as a boot floppy or CD-ROM on Intel (Pentium or Celeron) and AMD (K6, Athlon or Duron) systems.

To create a Windows Memory Diagnostic boot CD, follow these steps:

1. Download the Windows Memory Diagnostic Setup (mtinst.exe).
2. Once the download completes, run the Windows Memory Diagnostics Setup by double-clicking on the downloaded mtinst.exe file.
3. In the Windows Memory Diagnostic Setup dialog box, click the Save CD Image to Disk button.
4. In the Save CD Image dialog box, browse to and select the folder where you want to save the windiag.iso file, and then click Save.
5. When prompted that the file was successfully saved, click OK.
6. Use your preferred CD burning tool to burn the windiag.iso CD image file to a new CD-ROM.

At this point, you should now have a bootable CD that contains the Windows Memory Diagnostic tool.

To use the tool, place the CD into the computer’s CD-ROM drive and restart it. Note that the CD-ROM will need to be checked before the hard disk in the system’s boot order if an OS is already installed on the hard disk. If the computer boots from its hard disk before attempting to boot from the CD-ROM, you’ll need to access the computer’s CMOS Setup in order to place the CD-ROM drive ahead of the hard disk in the computer’s boot order.

Once the computer boots from the CD-ROM, it will automatically load Windows Memory Diagnostics and begin testing memory. When the test begins, press the T key on the keyboard to run the extended tests. Running extended tests provides greater testing granularity and will allow you to view errors by memory module if any errors are found. It will take several minutes for the tool to complete a single pass of memory tests. You should allow the tests to cycle for several hours or even overnight to confirm that no physical memory errors are present.

Note that the tool will keep cycling through a battery of memory tests until you manually stop the testing. If any failures are detected, you can view them by first pressing the P key to pause the testing. You will then need to press M to access the tool’s menu. If errors were detected, you will see two menu options that will help you identify the faulty stick of RAM:

• View errors by memory module
• View errors by test

When you select “View errors by memory module,” you’ll see memory errors that were detected for each RAM slot. The slot identifier will allow you to see exactly which physical stick of memory is failing or has failed.

The Windows Memory Diagnostic tool should provide you with the proof you need, Todd. Hopefully the guy who purchased the computer parts will spend a few extra dollars on quality memory the next time.