setup is:

Alienware
Windows XP Media center SP2
Core2Duo 6400 @ 2.13 GHZ
4GB Memory (acting like 3.25GB though) I forget the manufacturer
NVIDIA Geforce 7900 GT/GTO (256 MB)

I also just added a sound card just before it started crashing, it was a cheap sound blaster. Wouldn't think a sound card would start causing crashes but who knows. I'll download the latest drivers for that i guess.