[Solved] Why does the power supply affect sound quality?

It may sound odd, but it is no longer a question of "does it", but rather a question of "why does it". I just recently got a new video card so i could upgrade from the on board one, and it was one of the new nVidia GTX models, so i had to buy a new 750 watt power supply to be able to power it.

I replaced my old 350 watt power supply with the new one and had had my video card up and running for a about two days with no problem. Then, my audio suddenly changed to be scratchy and extremely low in volume when i turned it on on that third day. After agonizing over the cause for a week and trying many different methods to find out the problem, including removing the vid card (didn't work), changing the sound cards pci slot (didn't work), reinstalling sound and vid card drivers (didn't work),putting the card in another computer (worked fine), testing my speakers on other computers (working fine), and testing my speakers on my sound card on another computer (worked fine), i had nearly given up hope.

Then i got the idea of putting my old power supply in and when i turned it back on, my sound quality was PERFECT! I was downright stumped . Now I can't use my vid card without the new power supply in. So my question to you forum people is, what could the problem have been and how do i get my new power supply to work with my audio card?

I don't know what you mean by ripple or a quality unit. It is an ultra brand 750 watt that i got off tiger direct. I read the reviews closely and only one of the people had had a problem with it and theirs had arrived broken.

yes