New HSF, wont boot.

[budd1elee]

So I installed a new HSF today, it wouldnt power on at first, so I unplugged and reconnected everything. It ran for a couple hours then just turned itself off. At this point it wouldnt power on, when I hit the power button the fans would attempt to turn, and the led's would flash. I tried another PS, now the fans and LED's come on, but wont boot. Any suggestions. Ive tried everything I can think of.

Pentium D 820
Intel D945PSN
PNY 6600 PCI-e

 

[Atheus]

You didn't touch anything but the HSF right? You didn't scrath or knock anything? Then there's 90% chance it's overheating due to incorrect installation (wrong way round, too much thermal paste, really crappy thermal paste, etc) and a 10% chance you cracked the processor core...

 

[budd1elee]

Its a Big Typhoon. I used AS5. It ran for a couple hours then turned off.

As of right now it will only boot if I remove the mobo from the tray and set it on a carboard box. Has to be a short between the mounting bracket I would think. Now how do I go about fixing it?