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When I leave my desktop computer off for a period of time and then turn it on, the fan is very loud (in a way that makes me think something is wrong).

Oddly, if I shut down my computer and then immediately turn it back on again, the fan is quiet and docile. If I only restart the computer (not shut down then press the power button to turn it on) the fan stays very loud.

This problem began less than a week ago - should I be opening up my comp. tower to have a look at the fan? I have no idea why shutting down and turning on again solves it.

marked as duplicate by Karan, Shekhar, Ярослав Рахматуллин, Darth Android, Excellll Jul 18 '13 at 16:38

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  • 2
    The loudness would probably depend on the fan speed, which might be different in those two situations. In any case it really doesn't matter. If it's making a loud noise it means its bearings are worn out. You can try opening it up and oiling it, but the best solution would be to simply replace it with a matching one (fans aren't that costly anyway). – Karan Jul 15 '13 at 3:11
  • Not really a duplicate as that fan always had the problem, whereas this one can be fixed by turning off and turning on. Nevertheless, sounds like I need to replace the fan – nebffa Jul 15 '13 at 5:56

One can only guess, but it sure sounds as if it is failing. I would replace that fan. If @Karan will change his response to an answer I am glad to delete mine.

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