Buzzing noise coming from inside my computer while playing games

I just finished building my PC like a week ago. I just noticed there is a faint buzzing noise while playing a game (the noise also comes out from my speakers). I tried to pinpoint the noise and turns out it's coming from inside my computer.

The buzzing noise sounds like it's coming from either power supply or graphic card. I'm assuming it's the graphic card, because the power supply is already making a noise (like a hard disk. I searched a little, and it's a common problem for XFX Pro750w Core edition).

There is also another issue; when I turn off/on the power supply (switch), I hear a bump noise from my speakers.

I don't mind the noise but I want to make sure it is not something bad. Is it safe to ignore it?

I've uploaded the sound file which you can hear the noise (when I start a game): http://www.mediafire.com/download/njgxdb7qbkrmaxb/2.wma (There are 2 sounds: power supply and graphic card. The power supply's noise sounds like a hard disk, while the graphic card sounds buzzing.)

Thanks in advance...

Specs:

Motherboard Gigabyte Z77-D3H
Processor: i7 3770 3.4ghz
Graphic card: XFX HD7850
PSU: XFX Pro 750w Core edition

To this day I didn't know what was the root of the problem, but that was the sound of bad capacitors/chips.

It burnt a chip on my graphic card and it damaged the motherboard. I RMA'd the PSU and motherboard.

If something is unusual, don't wait until it's too late.

The buzzing noise from speakers and power on bump sound are normal and nothing to worry about. The one you've recorded is probably fine too. If you don't have overheating problems, I'd leave it like that for now and just check it every now and then. If it becomes louder over time, you should think about replacing graphics card's cooling.