i read in another topic that this might be the case. i have an a7n8x-e deluxe. i've tried to push the capacitators and inductors on the board around, but its still making the buzz noise. actually, i'm not sure where the noise is comming from, except i'm quite sure the mobo, cause i tried leaving no fans on.

Could also be the power supply, although I'd avoid doing on the PSU the test you've been doing on the motherboard...

Actually, I think this problem was addressed and answered here. In light of that, I'm going to lock down this thread.