Unexpected PC shutdown - possible causes

[wolluf]

Client's PC completely shuts down after random amount of time running (power just goes off). My first thought was overheating and when I saw the machine, it was running hot. I replaced the cpu fan, and temperature dropped to reasonable figure (c. 50C). Job done, I thought. Later feedback - apparently machine ran for 4 or 5 hours with no problems after I left (which is longer than it was doing) - but then shut down again. User monitored temperature - from then till next unexpected shutdown - never above 51C. I'm going back to look again tomorrow, and would appreciate any suggestions (my thoughts are currently that the cpu has been damaged by the earlier overheating, or a power supply issue). The machine is a socket 478 pentium 4 3Ghz with 512MB RAM - didn't check any other details.

Thanks

 

[BadFrog]

Anything in the event logs? Other than that I'd say your right on track. If they have a like PC nearby you could swap the CPU's to isolate that. But you already knew that hehe. When you power the machine back up does it report the unexpected shutdown?

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