so i upgraded my core i7 920 to a 940, now my pc keeps crashing, the video card a hd 5870 the fan goes on full speed and the vidoe goes off. after i restart the computer it boots fine. but it happen again sometimes it takes hours sometimes 2 minutes. the video card was working fine with the 920. all i can think of is that the PSU can't hadle the load of the faster cpu with the video card. as soon as i took the hd 5870 everything stated to work proper. i am using a old video card that does not need to be powerd by the PSU. what do you guys think? bad video card? PSU can't hadle it? cpu problems? motherboard perhaps? all was working fine untill i changed the cpu. i did run the 940 on prime95 for 4 hours no crash? with the old vidoe card.
It is very unlikely that your processor is bad, your power supply could be at fault but from the description you have given I would check the mounting of the heat sink and if you have a even spread of heatsink compound on the processor.