Robin;
Sounds like it could be just a noisy fan.
you could temporarily unplug the fan and see if the noise stops.
Don't unplug the cpu fan as you can overheat  the cpu on newer computers in
just a few seconds.
Perhaps if you would supply us with the brand and model of your PC
or the brand/model of your case and the approx. location of the fan in
question
someone on this list will be able to tell you how to remove it.
I just replaced a rear mounted case fan in a Micron system and it measured
120mm
yours might be similar.
They can be purchased from www.cyberguys.com or www.dalco.com
just to name just a couple of suppliers off the top of my head.
<>< Larry Fisk
         Fisk Computers
           Fruitvale, Idaho

----- Original Message -----
From: "Robin Smith" <[log in to unmask]>
Subject: [PCBUILD] Noisy PC


My PC has suddenly become much noisier. There is a definite
whirring/vibrating sound. I believe it's coming from the auxillary fan - not
the power supply fan. Is this something to worry about? Can it be replaced?
Is it easy to remove? If so, how? I was looking at it last night and
couldn't figure out how to remove it. Also, how do I know what replacement
to get?

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