High Pitched Squeal From PSU?

[predtetm]

I just bought an Antec SmartPower 2.0 SP-500 500w PSU. Right now it's a placeholder for my 250w mini-PSU that's in my Soltek SFF box, so the 500w is basically hanging on it's side. The problem I have is that upon powering up the PC, this PSU emits this HIGH-pitched tone, it reminds me of like a 15-20 kHz pure tone. It seems to be coming from the transistors/capacitors/etc from inside, not the fan. Does this sound normal at all? Maybe it seems louder becuase it's hanging out in the open? Any ideas?

 

[Hairy_Lee]

i get a similar noise from my system. in fact ive had it from all but two systems that ive owned. sometimes it can be a little annoying. im not exactly sure if it is the psu cos ive had it happen when one processor installed and not when another one is installed.