What does a dying CPU Fan sound like?

[Error]

So I get called on by the parents to "fix" their computer. It's making a noise they say. I get there and sure enough it's making an irregular noise. I suspect its the CPU Fan or the power supply fan. So I take it apart and get some compressed air, blow the dust off it. Wait a few hours, eat some dinner, and then power it up again. Noise is still there. Disturbingly it might even be worse.

So ya, how do I diagnose when a computer starts making noises outside the norm?

[Some Stupid Japanese Name]

YEAH! CPU'S ARE THE BESsssaaaargggghhhhglukkkk.

[Compass]

Open up the side while it's running and look around, with a flashlight if necessary. Shouldn't be too difficult to pinpoint where it's coming from. I've done this before with my graphic card fan. Was fairly easy to replace, too.

[kedawa]

Jam a pencil in each fan until the noise stops, then just leave it there. Problem solved!

[K3V]

It sounds like GRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR

[Frogacuda]

Dying fans don't make loud noise. Fans rubbing against wires or other shit make noise.

[Dyne]

Cheap fans with cheap bearings make grinding noises when they go south.

[Error]

So I did some further digging, it's the power supply. Thanks for all the help gentlemen.

[Opaque]

Dying fans sound like an onomatopoeia.

[kedawa]

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