About your "noise"...  I doubt if the hard drive would
make a lot of noise...  You should look in the case...
Some high quality 486s came with case fans...
(I have an "Overdrive 486-66" that will not run right
with the case fan off, or the cover off the machine.)
They are (at this age) prime candidates for noise...

With a "Pentium class" machine look at the CPU fan...
They are a constant noise problem for me. (Answer:
get a good one...)

Some people will tell you not to "crack open" a power
supply...  They will be right too, IF you do not know what
you are doing... (See warning below.)
I have disassembled and oiled three or four power supply
fans...  It is something you do for yourself, or friends
to "solve???" a problem without a trip to the store...
If the noise is too bad, and the bearings are "too loose"
all the oil in the world will either "gum up" or run out,
leaving you with the same problem... (Sooner or later...)
You "might" find a new fan that fits, but yours might
be riveted in, be too "fat or thin", and/or have soldered wires,
AND if the air flow on the new one is a lower rating, it could be
a FIRE HAZARD.
This would also be a concern with a fan with gummy/sticky
bearings that ran "slow"...

I have started to replace my power supplies in situations
like this...
                         Rick

----- Original Message -----
From: "A&C Thompson" <[log in to unmask]>
My comp, which is 3 years old, has recently developed a low, rumbling noise.

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