The best way to do this is to use a utility called memtest86+. It will run as a bootable CD in DOS, and will perform a series of systematic RAM tests to check all of your system RAM for errors.

To get memtest86+ running:
1. Go to www.memtest.org
2. Click on "Download (Pre-built & ISOs)."
3. Choose "Download - Pre-Compiled Bootable ISO (.zip)" and save the file to your desktop.
4. When the download is complete, right-click on it and choose "Extract All." You will end with a file that ends in .iso on your desktop.
5. Click Start > All programs > Nero > Nero OEM > Nero Express.
6. Choose "Disc image or Saved Project" in the "What would you like to burn?" section.
7. In the "Open" window, choose the Desktop in the "Look in" window, and choose the .iso file you just downloaded to the desktop, then choose "Open."
8. Leave everything on the default settings, and press Next when prompted.
9. Once the CD finishes burning, leave it in your drive and reboot the computer. it should boot automatically to the CD and begin running memtest. If not, reboot and press F-8, then choose to boot from the CD (which may show up as "PM Lite-On...").

When memtest is running, you will see several different tests run, and a status bar indicating if they passed or not. If any large blocks of red show up on the memtest screen, then there is an error in your RAM. Please contact Tech Support for further instructions.