Problem with new build

[Destinatus]

I just put together my computer on Thursday, here is the build I used: http://forum.pcmech.com/showthread.php?t=179064

My problem is that my computer has just turned off twice now. Both times were when I was playing a PC Game, I'm not sure if that's just a coincidence. I think that it might be that my processor is getting too hot. I got an error during boot up once that said my CPU temp was too high or something like that. Another reason I think it might be that is because when I was putting the heatsink and fan on the CPU I didn't clamp it on right and had to redo it several times, somewhat irritating the thermal compound. Should I buy some arctic silver or something? or maybe my case needs more fans, I'm not sure.

EDIT: I just ran the StressCPU test with ORTHOS and CoreTemp showed each core at 85 deg and around 59 deg after being idle for about 10 mins

[Cricket]

Sounds like the heatsink isn't installed properly. If you installed the heatsink while the motherboard was already mounted in the case you probably had a difficult time with the locking pins. The LGA775 heatsink is easier to install if you have the motherboard out of the case. LGA775 heatsink installation tutorial.

Cricket

[Destinatus]

Thanks cricket, that seemed to do the trick. Temperatures dropped significantly. At least it looks like I'm not the only one who had troubles with the LGA775 heatsink.