Best way to isolate fan noise?

[Seiken]

Sometimes (about 75% of the time), when I power on my computer, one of the fans makes this hideous sound for like 5-7 seconds and then it goes away. I've tried booting with the side panel off to see what was causing it.. But it's so hard to tell with the CPU heatsink/fan combo, NB fan, ABIT OTES fan and the Radeon fan so close to each other.. oh yeah, can't forget the case fan as well.. so what's the best method of narrowing down the problem?

The noise sounds like on of those old Air Conditioning wall units.. best I can describe it

There are no wires touching any of the fans and I've blown them clean

 

[hkfnstang]

oil your fan's bearing, it might help

 

[jseber1982]

just touch the fans one at a time to stop them and see when the noise stops, easiest way i can tell to find the noise.

 

[daappleby]

just touch the fans one at a time to stop them and see when the noise stops, easiest way i can tell to find the noise.

That's you best bet. If your a sceerd to touch em just unplug the ones you can (not the cpu one though) once you have em all unplugged, plug one in at a time till you hear it again.

 

[Seiken]

I'll try that next time. Thanks. I'm thinking it's the CPU fan.. Zalman CNPS7000A-Cu ($40 replacement).

 

[Seiken]

Seems like it's the northbridge fan causing the noise. Which isn't too bad since it's a $6 replacement part on ABIT's parts store. The bad part is having to remove the Zalman CNPS7000A-Cu in order to remove the NB fan.