Ken Blake wrote:

On Mon, 18 Mar 2019 08:13:35 -0400, Art Todesco
wrote:

When I start to hear my CPU fan speed up and then down, it has always
been that the fins on the CPU are clogged with dust. A quick vacuuming
and all is quiet again.

As I understand it, vacuuming inside a computer case is a dangerous
thing to do. You run the risk of a static electricity discharge frying
the CPU or other components.

Much safer is blowing out the dust with a can of compressed air.

You also get concentrated higher pressure air delivery from the straw
tip from canned air than with the far more huge diameter of the vacuum
hose.

I do sometimes use a vacuum but that's only when I blow out the
computer's dust inside the house. I attach a wide floor tool to the end
of the vacuum hose and hold it to hover a few inches away from the
computer. It's to catch most of the dust that I'm blowing out of the
computer, so it doesn't end up in the room. The vacuum never touches
the computer. For the annual springtime dusting, I disconnect all the
cables and take the computer outside to dust it out using compressed air
(and NOT from an air compressor which is way too high for pressure but
by using canned air).

Yes, there are computer vacuums (and bigger than those rather useless
ones for cleaning the keyboard) that are designed to not produce static
(very expensive); however, they still cannot suck the dust out of the
tight fins of heatsinks. Those little computer dusting fans have little
suction, so they suck (figuratively).

I do use ear swabs when I dust the computer. One use is to keep the
fans from spinning when I blow compressed air through their fins. Do
not allow an unpowered fan to spin when blowing air through it. Another
use is to scrub the fins of the fans. At speed, dust will stick to the
fins and blowing (or vacuuming) won't budge it. The limp bristles on a
little computer vacuum won't dislodge it. The stuck-on dust can
unbalance the fan. When I hear a fan making more noise, cleaning it
(which includes scrubbing off the stuck-on dust) makes it quiet again.
Out of balance fans make more noise.