Hi recently my pc has been restarting (sound joggs for a few seconds then the pc just cuts out and restarts) 5-10mins into doing intesive tasks - for example when playing a game or watching a video clip on the internet. i have recently upgraded/replaced my ram (to 2gb) although have ran memtest and no problems were found.
i am running vista and have also upgraded the sound and grahics cards but this was a long time before this started happening.
. They sound OK - so as has been suggested another culprit may be the PSU.
However it could also be a software problem.
Replacing the PSU is quick and simple, but will cost you some cash. Don't buy the cheapest you can find, it's false economy - get a decent branded one. 450watts would be more than enough, higher won't be a problem but don't spend more just to get higher.
Read here click here aboiut disabling the automatic reboot, so that you can see what error may be causing the system to shut down. And how to troubleshoot such issues.