Recently, I've been hearing an annoying buzzing noise coming from my tower, and I'm 90% sure my power supply is causing it. The noise comes on and off for periods of time - ten minutes buzzing, ten minutes silent. I'm currently trying to figure out exactly why it's buzzing. The noise seems to go away when I lay my case sideways, and it also goes away when I push quite forcibly on the power supply itself (from the back of the tower). I opened my case and applied different pressure on the PSU as the computer ran - this changed the noise as well.
Would that make it a fan hitting a wire, then? Google results seemed to imply a buzzing noise meant my PSU is bad, that it wasn't just hitting a wire or something.
Halp!