2

When any hardware accelerated application is rendering a frame (or many of them) a very short noise is coming from my speakers. This can be a game, a WebGL application or XBMC. When the application/game is rendering many frames per second (like most of them do) the noise is a continuous buzzing that gets higher pitched with higher framerates. This applies to Linux and Windows, so I'd assume it's a hardware problem.

The current hardware in the PC is:

  • CPU: Core2Quad Q9550
  • GPU: Radeon HD 5770
  • RAM: 2x2GB DDR2
  • Motherboard: Asus P5QLD PRO
  • PSU: be quiet! Pure Power 530W
  • Screen and speakers: Old 720p LCD TV connected via VGA and aux cable

Muting the TV stops the noise, muting Windows doesn't.

I tried replacing the PSU first (used a Tagan 700W PSU before) because I thought it was a power problem. It wasn't. I tried replacing the motherboard (used a ASUS P5B SE before) next because I thought it was a sound card problem. It wasn't. I tried the GPU in a different PC because I thought it was a broken graphics card. It worked perfectly fine in the other PC. I thought it might be interference, but moving the audio cable around changes absolutely nothing.

I tried using an HDMI cable instead and that did work, but is not an option since my TV has only one HDMI input and I need that for my PS3.

1 Answer 1

0

It sounds like your audio card/cables are improperly insulated or isolated.

If the cables are not properly shielded, or are too close to your graphics card, it is possible that the wires will pick up on any electromagnetic field and you will hear it through your speakers.

The fact that using an HDMI cable fixed it, implies the issue is not with the GPU or audio card, if you have one, but rather with something explicitly related to the audio cables.

Now another possibility is that you are getting interference in the wire, due to poor grounding or electrical flashback. Try checking all the connections on your mobo, particularly those around the GPU, audio card(if applicable), and the connector for the audio cables, though checking all connectors isn't a bad idea.

It's possible, that your mobo isn't properly isolating the various devices and cables, and what you are hearing is voltage spikes that aren't being absorbed by the internal mechanisms designed to do so. I don't really know how to test for this, but if all else fails, it is something to look into.

For another data point, it would be interesting to see if you took the GPU from the other computer, and stuck it in the PC with issues, and see if that changes anything. And another question, if you move the aux cable from the headphone jack in the front, which I presume you are using, and plug the speaker into the jacks in the back, does anything change?

EDIT: I just realized something. Does the sound go over HDMI too, or just video? Try a new VGA cable, it seems possible that the leak is occuring at the GPU-VGA connector. Inspect the connection to see if you can find any wires that have cracks or are broken, etc.

1
  • I'm not at home right now, so I can't try everything you suggested. But I can answer a few of those questions: I was using the audio jack in the back because the one on the front is broken. HDMI was transporting audio too. When I plugged in my headphone instead of the TV into the same audio output I didn't hear the noise. When I unplugged the audio cable from and just held it against the USB plug I heard the exact same noise with every frame again, but not the regular audio... obviously. So I guess your insulation idea is probably correct.
    – Robber
    Nov 4, 2013 at 9:16

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .