Dimension 8100 Power Supply Squeal

My over 5 year old (and out of warranty) Dimension 8100 has always made a loud squealing noise from the power supply -- but only when it's powered OFF.

By searching the board, I know I'm not alone.

Since the machine has a lot of life left in it, my workaround has usually been to pull the plug from the back of the computer when I'm not using it.

Back when it was new (and under warranty) I had the power supply changed.

Twice.

Squealed each time. So I lived with it, and chalked it up to poor Dell design -- the same poor Dell design that crufted...er, crafted a completely unique power supply for the 8100, making generic replacements out of the question.

I know that I could use the "Silencer 410 Dell-1" from PC Power & Cooling to replace my power supply, but at $99.00, that's a steep investment in a 5+ year old computer.

Any ideas? I've been diligent about cleaning it inside...there's not a speck of dust to be found.

Anything to tighten? Loosen? Fiddle with?

Any suggestions appreciated....