weird noise...

[Lemon_Lime]

mm... well, yesterday i heard some weird noise coming from my computer, like something vibrating or something... i think it was from the power supply but im not sure...
anyway, i turned it off and after a few hours turned it back on, and after a few seconds it started trrrr-ing again...
so i turned it off again and waited another few hours, but this time when i turned it back on i waited a few minutes at startup before i put in the bios password, and it didnt make that noise anymore... it now works fine but i just wanted to know what that noise was, and what should i do if this happens again...?

[Raptor]

Probably a failing or misaligned fan. You're going to have to open your case and see if any of the fans are acting up.

[street1 (RIP)]

Have you ever done a complete internal cleaning?Like raptor says"It's probably
a fan, or a fan.You,ll need compressed air.

http://www.librarysupportstaff.com/4compcare.html#clean

[Lemon_Lime]

ok, ill try that... thanks...

[patio]

As always whenever opening the case up make sure to take electro-static precautions...ground yourself properly before touching anything and remove all power to the machine.

Do not use a vacuum in there.

patio.  8-)