A few weeks ago my computer began to power off unexpectedly. No warnings, no error messages, just like I simply unplugged it. My system would shut off like this about every other day, but then it started shutting down more often, like once a day, or twice a day. The intervals between shuts down kept getting shorter until I couldn't even load windows without the system powering off. I could enter the BIOS and I noticed the CPU temperature was 200-210 F. At this point, I could leave the computer off for about an hour, and it would then start up and run for about 10 minutes before powering down. The CPU temperature wasback to around 200F after every shut down. After several failed attempts, I managed to run a system restore before the power shut off. After I did this, everything seemed to work nicely. Until I ran a virus scan. Midway through the scan, the system powered down, and led me into the same shut-off cycle I was in before. This time, the only way I could get a system restore to complete was by restarting with "Windows Domain Controllers Only." After the restore, the system again worked fine...until I tried another virus scan, this time with a different program. It powered down, cpu temp was high, same deal. Well, I system restored again and quit DIDN'T do a virus scan and now my system is semi-stable. It will power down unexpectedly almost every day, and I will run a system restore every couple of days. Interestingly, my friend (who is on the same network) had the same program on his laptop. After a complete reformat, his computer quit having the problem. I want to avoid a reformat. I thought it was a BIOS virus affecting CPU fan speed or something so I flashed the BIOS, but that didn't improve anything. I doubt it is a hardware problem, because if it were, a system restore shouldn't have any effect. Anyone have any ideas?

99c = 210f ,that's hot. I would be putting a new heatsink/fan on the processor, one that connects to the power supply using a molex connector. (same power connector as the cd-rom & hard drive) untill I got it sorted out. virus scans working etc.

i have exactly the same problem with my laptop. i thought it was a virus or something. i was trying to search for patchnow.net. i had a pop up ad saying "protect yourself from unexpected shutdowns". i bought a notebook cooler, but it doesnt change anything. i think formatting the pc and installing the OS again is worth a try. please help.