You replace them. I'm unsure what else we should do since these fans are not repaired.
PS. In decades, cooling fans have not been a software or setting issue. Some PCs allow speed control but that does not fix old loud fans.
So just a little while ago I plugged my Dell Optiplex 9010 AIO in and it did its power up test and passed it fine,but when I turned it on I got a message saying the power supply fan had a failure.So I unplugged everything and took it apart and just unplugged the fan from the board and plugged it back in.the fan started spinning again but now it’s noticeably louder than it was before.Its not even like broken loud it’s just spinning faster than before.I have 2 of these computers and I checked the other one and it’s much more quiet.So I decided to clean it.no difference...Im not sure if its anything to be concerned about or if it’s anything I can fix.I feel like it’s going to burn out faster now that it’s spinning faster than usual.Any advice?Should I swap out fans and see what happens?Is it a software/hardware issue?Should I but a new fan?Or is it safe enough to let it be?

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