The question by itself is virtually meaningless. You should have asked folks to name the brand and what they did or would do to fix it.
Noises can come from many different sources. For example; pre 2006 DELL Dimension 8000 series are well known for LOUD cooling fans. Dell's replacement in late 2205 & early 2006 - the E510 - is so quiet you cannot even tell if it is on. However, the top line DELL XPS Desktop sounds like a jet engine in reverse thrust since it has multiple fans trying to cool down all the dual core et al gaming processors and processes.
The question is: what can be done about it - whatever the source and what should you buy if "quiet operation" is a priority for you.
How would you describe the noise level of your computer?
Very noisy (how so?)
Noisy (how so?)
Acceptable (what's acceptable?)
Quiet (describe it for us)
Very quiet (like nothing is on?)
Other (please explain)

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