Coil whine problem

[G-Sharp]

Hello guys

I am having a frustrating problem with coil whine in my system and I was just wondering if you could help me out.

Well, I know that the 3 possibe sources are PSU, GPU or motherboard. I have now ruled out GPU as being the problem as I have just ordered a new one (HD 7850) that I have recieved today and I still get the coil whine.

My AX850 PSU makes the noise as well as the area around my GPU, but when I use an older PSU that I have laying around, a faint noise (I have to get my ear up to it) only comes from the area around my GPU but no noise comes from the PSU.

I've also noticed that when idle, my AX850 makes a faint noise, while the older PSU hardly makes any.

The noise is loudest when I am running 3D programs like games and 3D benchmark, and stops when I am on 2D, like load screens or desktop.

Does anyone have any idea on what it could be? I don't have an extra motherboard laying around, so I really am stumped.

 

[G-Sharp]

I'm thinking there must be something wrong with the AX850 atleast, as my other PSU doesn't make the noise. But then, why am I still getting the same noise (although pretty faint) coming from the area around the GPU when using two different GPUs?

Do you think there may be something wrong with the motherboard, or am I just extremely unlucky and both GPUs have the problem as well as my PSU?

 

[G-Sharp]

I think the first step should be to RMA the PSU, as it is making the most noise when on load. It's something I really cannot live with. My older PSU makes no noise what-so-ever.

Then it's between that GPU and Mobo. But if it remains faint, then I may be able to put up with it.

You guys think those are the right steps to take?