Thread: High pitch noise from PSU - not all the time
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Eeyore Eeyore is offline
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Default High pitch noise from PSU - not all the time


Michael Kennedy wrote:

"Eeyore" wrote
wrote:

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

Quite likely to be the ferrite cores in the PSU 'singing' as a result of
magnetostriction.


How do you solve this? Will a coat of varnish stop them from singing? I have
a psu that sings in the 14-16khz range when it is on standby.

Once you get a noisy one it seems to require replacement. The varnish might do
it if it was a vacuum varnish process !

Some ferrites also 'hiss' btw due to controller chip behaviour AIUI.

Graham

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