PC keep turning its self off when playing Games?

So my PC keep turning its self off when playing Games, first thought was over heating.....but no, CPU, GPU all under 60°

So tested RAM......No errors after 7 sweeps with Memtest.

have a 800w PSU, so cant lack of power (only running 1 GTX 260 GPU, and quad core phantom)

Is there nothing I can run in the background that will log the reasions for the crashes?

Its driving me mad!!!!!!! :x

have a 800w PSU, so cant lack of power

This statement is true, if the Power Supply isn't defective in some way. It might be worth using a multi-meter (or other means) to monitor the 12v and 5v rails while it is under load. Might be when idle the supply is fine, but under heavy load one of the rails is dropping enough to trigger the supply to shut down.

Are you sure its not the "over temperature" after all? Could be the settings are set too low in BIOS?

I dont know what OS you use, but windows have an event viewer, that might give you some clue...if it manaages to log it before shutting off that is. For XP: windows-help-central.com - windows help central Resources and Information. I'm sure I wrote something else in the run box, I just dont remember what atm, its been ages since I used that.

Maybe it's just bored with wasting it's brain power trying to operate as slow as its human operator

Are you sure its not the "over temperature" after all? Could be the settings are set too low in BIOS?

Pass.....bios gives me the fear!

I dont know what OS you use, but windows have an event viewer, that might give you some clue...if it manaages to log it before shutting off that is.

Im using win7 so will have a look

Ran stress tests on my GPU and CPUs

Furmark stress test for 30min+

FPS
min=64 max=635 average=82

(temps went up-to 84 after about 10mins then stayed stable for the rest of the test at 84) - no crash

IntelBurnTestV2

Processor: AMD Phenom(tm) 9950 Quad-Core Processor
Clock Speed: 2.61 GHz
Active Physical Cores: 4
Total System Memory: 3327 MB

Stress Level: Maximum (930 MB)
Testing started on 26/09/2010 20:04:05
Time (s) Speed (GFlops) Result
[20:08:45] 34.697 22.1286 3.376860e-002
[20:14:04] 34.412 22.3115 3.376860e-002
[20:19:28] 33.891 22.6547 3.376860e-002
[20:24:49] 34.150 22.4827 3.376860e-002
[20:30:11] 34.033 22.5600 3.376860e-002
Testing ended on 26/09/2010 20:30:11
Test Result: Success.

That's pretty hot, take the cover off and see if your heat-sink and fan aren't covered with dust, as that should be the probable cause of the overheating.

dang it you jinxed me!

minding my own, playing GTA 4 and it shuts off, temp at 84c (personally anything over 70 is pushing it)

grumble I dont feel like dealing with this right now. I just cleaned it out and replaced heatsink goo a week ago, was running fine at 52 under full load