Persistant Blue Screen of Death?

I embled my desktop about three weeks ago. Specs: Intel Core 2 Duo, Asus P5N-E SLI Motherboard, 2 x 1GB Crucial Ballistix RAM, Nvidia 8600 GeForce Graphic's Card, 750 W Power Supply. After installing Vista Ultimate, I would frequently get the Blue Screen of Death and umed it was a driver issue. The screen never lasts long enough for me to record what the error is. The screen can pop up at any time, such as playing streaming video, transferring files, using iTunes. I wiped off the hard drive and installed XP for a more stable OS, but I still occasionally get the BSOD and cannot install certain programs such as Visual Studio 05' and Adobe Master Suite. I know these programs work as they installed correctly on my laptop. I updated the BIOS and have no other external devices or programs on the desktop that are not on my laptop (which works just fine). I have not configured any settings in the BIOS, and most are set to the "auto" detection settings. Any suggestions would help.