Sounds like you have a dry bearing in one of the fans in the PS. Most PS's
use bushing/sleeve type bearings which usually only last approx 1 to 2
years. My experience has been the fan blowing out the rear usually goes
first. You can either replace the fan for 8 to 10 dollars or you can
carefully peel back the decal in the center of the fan blade which will
reveal a small hole in the center. Put 1 drop, I repeat 1 drop of a good
quality light oil in the hole in the center of the fan. A good quality
sewing machine oil or 3 in 1 oil has worked good for me. They usually go for
another year or two before they act up again.
Hope this helps.
John Dinges

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