Computer shuts down

[volanis]

I've asked this question a in a couple of different forums because at first I thought my problem was overheating so I addressed the issue bu taking all the necessary steps to resolve an overheating issue, ie. cleaning off the cpu and applying fresh TC, removing dust from heat sink and fan(on the gpu also). That didnt work so then I though it was the PSU...so i got a newer more powerful one. Didn't work. Then I thought it was a memory problem....memtest came up with no errors. I updated all my drivers, did virus scans, spyware scans and found nothing. I will say that my cpu shoots 30c to 60c in a matter of minutes of playing a game like say Daragon Age 2. I'm not sure if that's why it's shutting down...I have seen it reach 65c with furmark no problem.
Can anyone figure this out please?
heres my specs:

amd ll x2 3500mhz
4 g ram
motherboard biostar ta785g3hd
amd radeon hd 6670
6500watt psu

 

[scout_03]

check if your fan spin on the cpu to the speed it need for the cpu temp ,did you activate some king of temp control in the bios like the cool and quite in asus .