The PSU works, but shortly after powering on (either in the G5, or by shorting the power-on pin to ground) it begins buzzing loudly. It also makes the LED lights connected to the same circuit flicker. It's definitely a buzzing, not a high pitched whine.

The buzzing seems to come from the high voltage side of the board, perhaps from the white relay. Could the relay be bad, or could the 5V supply be bad enough that it's unable to keep the relay on? Any pointers to help isolate the issue? Thanks!

Other info: API2FS34, ID 291, Date B0404

Hi! Read the forums for a while, finally decided to join. I enjoy repairing electronics and older/vintage computers.