Windows Memory Diagnostic

[Tac2i]

For those that are experiencing game or PC crashes, this tool from Microsoft might help you diagnose if your memory chips are the source of the problem.

http://oca.microsoft.com/en/windiag.asp

Note also that if you have memory chips from different chip makers installed in your system, that can also be a source of problems. In addition check for dust buildup and execessive heat.