>I was just siting here working when suddenly my PC rebooted. Now, after I start up, and while it's still sitting at the login screen, the Blue Screen of Death flashes and the PC reboots..It all happens very quickly wih no time to do anything. I can reboot in Safe Mode, but what do I do now?

Try to download memtest86 and use that. Also, depending on the manufacturer of the hard drive, you can usually download some sort of diagnostic utility.