What's wrong. everything runs top notch, PSU makes a buzzing sound? maybe a fan runnin at low RPM?

Question

Specs are in my sig,
Everything runs A+, I stress tested with Prime95 and memtest 86 with 0 errors and pass 3dMark 2001SE and 3dMark 03 with flying colors and play all my games with everything maxed out without one single hiccup.
My power supplies voltages are A+ too, I'm thinking that the buzzing is caused by the bottom fan on the PSU, as it's thermaly controled, it's running at a low RPM because the temperature in my case is very cool with all the fan's I have.
1 x 92mm @ back
1 x Exhaust fan @ back
1 x 92mm on windowed side panel
1 x 80mm @ bottom front
1 x 80mm on opposite side panel blowing on HDD rack
1 x ThermalTake Silent Boost K8 HSF
So ya everything runs very cool, do you guys think it's the PSU's bottom 92mm fan running at a low RPM because the temp is cool in my aluminium case?
Thanks for any advice guys  

Answer 1

Quote
Originally posted by frank2036
But ya, when I run my PC, the tone of the buzzing changes when I'm doing something, like HDD activity, launching a program, anytime I do something it changes the pitch.
I use an Enermax 365P-VE FC, and I notice a buzzing sound too.  It is very high pitched noise that increases when the hard drive is active or when I am doing something thats 3D intensive.  It doesn't sound at all like a fan.
The noise bothered me so much that I went out and bought one of Enermax' new "Noisetaker" 420W power supplies.  When I installed the unit, I noticed that the buzzing sound was even worse than my old power supply!
I'm no engineer, but I think the high pitched noise is coming from the power supply's inverter/diode.  Hard disk drives and video cards require tons of current, and it is no coincidence then that when these devices are active, the power supply is working harder, causing it to make even more noise.  A bigger power supply (reqiures a more powerful inverter?) and would probably cause even more noise, as was my experience with the 420W Noisetaker.
Do us a favor though, when you talk to a professional about your power supply, ask them about the power supply's "inverter" or it's "diode" (I forget which is which, but I know one is used to convert AC into DC which is what a power supply does)  and how much noise it would typically make, I'm almost sure that is the source of your buzzing sound.