Case fan making strange sound

jexorz

Distinguished
Nov 26, 2013
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Ok so for quite some time now the front fan on my computer has made this awful sound for somewhere around 60-90 seconds after the power is turned on. It used to only happen on the first boot up after dusting out the inside. and slowly grew more and more frequent. and now happens each time i turn the computer on. I know its not gridning, and i know there is nothing stuck in the fan... and it seems to spin freely... im rather stumped as to the cause of the sound.

i know i should probably replace it, especially with summer on the way but i dont see how to get at it. its nearly completely encased in the cheap-o case i got and i have no idea how to safely take it apart enough to put it back togeather
 

Paperdoc

Polypheme
Ambassador
The sound and pattern you describe VERY likely are signs of the fan's bearings wearing out. When wear first becomes apparent it is because they have worn to the point that the gap between shaft and bearing is wider that a new fan. That gap changes with temperature, and is widest when the fan is cold from being off for a while. When you turn on after being shut down, the shaft rattles around in the bearing, causing the noise. But it also heats up, and soon the gap narrows and the noise stops. It does not come back until the fan cools down. But as time goes on, the wear gets worse and the noise starts to last longer as the gap widens. At some point the wear will become much worse and the fan will fail completely.

So, you have a timely warning. Plan on replacing that fan, and find out how to so it, before the final failure.
 

jexorz

Distinguished
Nov 26, 2013
121
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18,695
That does sound pretty probable. I think im probably going to end up replacing my entire case as it was the one thing i skimped on when i built this computer. I guess ill shop around for a decent case that comes with some new fans i suspect one in/out fan probably isnt enough either way