Strange noise

[auda]

today when i tried to open my pc , a strange noise came out ( i cant describe it )then some fan (i think the processor one -i dont know as it is inside the case ) made a sound as it is working @ it's 100% speed then everything calmed down

rebooted several times but nothing happened (normal start )

specs:
core i7 860
gpu sapphire 5850
2X2 kingstone ram 1300
psu osz stealth & stream 600w
case cooler master 330

so what do you think ?
(well another small problem happened in the past , it may help you to analyze the problem when it first came it was with 2gb ram only & later i bought another 2 gb and when i put it in , the mobo gave an alert so i changed it's places several times until everything become normal )

 

[Zinosys]

Welcome to THF.

Please try to describe the sound! Is it high-pitched, is it a beep, rattle, what?

So, what exactly happened? You heard a funny sound, your fan then went up to 100%, then you couldn't boot anymore? That doesn't sound good...

Did you make any recent hardware or software changes to the computer?

Did you smell anything funny when you opened your PC?

Did you touch any part of the board (or anything for that matter) when you opened your PC?

Cheers.

 

[Ubrales]

What heatsink are you using for your i-7 860 CPU? Earlier I had a start-up noise that subsided after about 2 minutes. I re-seated the heatsink and the noise went away.