If possible i would try to get it at the same time as the PSU. You will end up redoing some cables at that time so mine as well through in the motherboard and get it done with less hassle.
If your PSU is really making the sounds that you spoke of, its time for a replacement ASAP. The last thing you want is all of your expensive components fried.
If your PSU is really making the sounds that you spoke of, its time for a replacement ASAP. The last thing you want is all of your expensive components fried.