The other day, an unusually hot day(and I don't have AC) My processor (Pentium D 945) temperatures reached 73 degrees C and my motherboard (Intel 965WH) reached 71 degrees when trying to load a new graphic intensive game. I closed the game and the temperatures returned to normal. I turned off the computer for the night to let it cool down. Before I turned the computer on in the morning there was a power outage (so with my computer was off, but still plugged in when the power came back on). I don't know if it was the overheating or the power outage that caused my problem, but now I am unable to boot my PC. At first the system would run for a little bit and then the motherboard would continuously beep(which means a processor error) so I reseated my processor and reapplied thermal grease(artic silver Ceramique) and reseated my CPU fan (Artic Cooler freezer 7). Now the motherboard gives 4 beeps (which mean it is grounded), but I have looked over it several times and checked many things and I can almost guarantee it is not grounded. I know the easy solution would be switch out the motherboard and then the processor, but I don't have ones to switch at my disposal. So I am wondering if there is any other way to tell what my problem is and if I have a fried motherboard or processor, before a spend a large chunk of money trying to swap each part out to find the problem.

Thank you very much for your time and any help is greatly appreciated.

Quite possibly, there was a surge when power came back.

Less likely but possible is that the CPU temperature rose too far when it was switched off because the fan went off at the same time. Like on those projectors whwre the fan stays on for a few minutes to get into a cooling cycle.