My friend's PC just freezes on the main startup screen when it displays the motherboard manufacturer logo.In this case it's intel. After that nothing works. Keyboard also stops working. Obviously i'm unable to enter BIOS setup. Earlier it used to freeze when the windows was loading or a few minutes after the booting of windows.Before freezing ,the system used to slow down badly and then it just used to freeze.Now,the PC runs only once or twice a week and whenever it runs it slows down and then freezes again.
I've checked the RAM,PSU,Cables,Hard disk and Processor and everything seems to be working fine.Only thing that i've seen that could be a problem is the thermal paste on CPU.It has completely dried and vanished and i think this problem is all because of overheating.What's your view regarding this problem ?? Let me know.
His system config is :-
CPU overheating will shut the machine down to avoid damaging the CPU. You can remove the CPU Heatsink and fan, clean the processor and the heatsink with rubbing alcohol and coffee-filter paper (it's lint-free), and then replace the thermal paste with Arctic Silver or some other brand of your preference. The instructions for various Arctic Silver thermal past products is here.