wrote in message
oups.com...
My PC (Dell Precision 370, about 14 months old) is emitting a high
pitched tone; I'd say between 8 and 12 KHz but that is a guess; that
guess based on recall of acoustic-coupler modems. Loud enough to be
annoying; hardly loud enough do much about.

It is not the (19 inch flat analogue, not CRT) screen and I have
isolated other items like USB disks.

Reluctantly, I switched the machine off and the noise disappeared. The
machine has been switched off only once before; not green, I agree, but
I don't like switching off critical machines.

A transformer or other power supply part?

There may be a momentary slight modulation of the sound when the screen
changes, hence the initial suspicion of the screen.

Laziness, I agree, but I'm putting off dismantling everything and
opening up the box; and given the frequency, it will be difficult to
pinpoint anyway.

TIA,

Jon C.


I've been in IT for years now and something like this could be too numerous
things to mention and not really worth speculating about - certainly not
without seeing it.

It really is process of elimination, starting with the easiest most obvious
things. The casing, for example can vibrate, especially if something is
touching it. Electrical interference. The fan, etc, etc.

I visited one user recently who had logged a call saying her mouse wasn't
working. After noticing no lights or display on her PC it quickly turned out
it simply needed switching on! I'm not implying for one minute you are of
the same callibre, but some faults aren't always what they seem.