A carefully placed, non-conducting rod (a thick wooden stick
will work) gently pressed on the PS's components one at a time
should find the problem. More than likely it's one of the toroids.
Put a small dab of silicone at the base where it meets the board.

"RD" wrote in message m...
I have an Enlight 350W power supply that has been doing a fine job for
several years. In fact, it is still doing a good job but has recently
developed a high-pitched whining noise. It is not the cooling fan. I opened
up the supply, and the noise seems to eminate from a section containing some
good-sized toroidal transformers. There are a couple of power transistors on
large heat sinks nearby as well, so I don't know which component is the
noise source. Anyone have any ideas on how to repair this problem? I was
thinking of squirting a bunch of high temp silicone all over the components,
but thought that might not be good because it might cause the components to
heat up too much. I have a new ps on the way, but would be interested in
hearing theories on how to fix this one.

RD