Buzz when GPU is loaded

[MKreroo]

Hi, I have recently noticed my speakers buzz (quiet but noticeable) when the GPU in my PC is under heavy load (>200W), the buzz doesn't show up if GPU isn't under heavy load.

The audio chain is PC -> USB Isolator -> Qudelix 5K -> Speakers

The same buzz appears even if the 5K is instead connected through BT, bypassing any physical connection to PC.

The isolator is for eliminating ground loop since 5K to speakers are running on SE, so I am curious what would be a possible source of the buzz.

 

[dasdoing]

sure it's not coming form the card itself?

 

[Deleted member 48726]

Are your PC power supply grounded and is the supply cable to it with a ground pin and is it connected to an outlet with a ground?

 

[MKreroo]

Are your PC power supply grounded and is the supply cable to it with a ground pin and is it connected to an outlet with a ground?

Yes, ground pin is present on all.

sure it's not coming form the card itself?

well the buzz is coming from speaker, disappear when they are off. Unfortunately my gpu does also have coil whine though I place it where the whine isn't audible

 

[Deleted member 48726]

I suspect it can't really come from any other place than inside of your PC. And it could be from both the PSU or it could be when the motherboard supplies power via. PCIe to the GPU.
Maybe take a look at your routing of power cable from the PSU to the GPU. Rearrange it and see if it makes the noise better or worse.

 

[Rhodo]

Wow I'm really curious about this... You get this on direct connection and on bluetooth? Wild. I'm not quite following the acronyms (5k?) so please bear with me if I ask something redundant. Are you plugging the PC and audio equipment into in the same power source? Power strip, wall plugs, UPS? When you run Bluetooth is it still also plugged into a physical connection or did you disconnect that? How close is the audio equipment to the PC?

 

[OnLyTNT]

Does your pc case have a window?

 

[voodooless]

It almost sounds line one of the analog audio inputs are getting digitized and mixed in with the other audio.

To test, use player software with exclusive access to the audio hardware, either though ASIO or WASAPI.

 

[Deleted member 48726]

It almost sounds line one of the analog audio inputs are getting digitized and mixed in with the other audio.

To test, use player software with exclusive access to the audio hardware, either though ASIO or WASAPI.

You can be right but how does this correlate with the noise being audible only when the GPU is pulling power?

Come to think of it @MKreroo to troubleshoot whether the noise is coming from your PC PSU or from the GPU you can try to stress test your CPU. Maybe it doesn't draw enough power to really reveal the issue but it can be worth trying. Use this online CPU stress test while playing music-->

CPU Stress Test - An online tool to test your CPU stability | CPU Expert

CPU Stress Test is a CPU stability test that allows you to test online your processor at heavy load

cpux.net

 

[voodooless]

You can be right but how does this correlate with the noise being audible only when the GPU is pulling power?

Because analog inputs tend to pick up noise easier, especially if they are not terminated or high gain, like for instance a microphone input. This was a thing 20 years ago when I still used Windows, likely it still is…

 

[Deleted member 48726]

Because analog inputs tend to pick up noise easier, especially if they are not terminated or high gain, like for instance a microphone input. This was a thing 20 years ago when I still used Windows, likely it still is…

Okay. Easy test is to short unused inputs with RCA.

 

[Dunring]

It's coil whine making that sound. You can sometimes undervolt it to reduce it. If you have optical out then run it to a DAC located as far from the PC as possible. I moved my tower below the desk also and can't hear it now. Putting a Febsmart USB 2 port card at the bottom away from the video card up against the shielded side of the power supply for a quiet noise floor on those ports.

 

[antcollinet]

What is the 5K? A DAC?

Are the speakers powered? So unbalanced interconnect from the 5K to the speakers?

Are both the 5K and the speakers grounded (3 pin power)? Are the 5K and PC connected to the same outlet?

 

[staticV3]

Sounds like EMI/RFI emitted from the PC is finding its way into your speakers.

 

[antcollinet]

Sounds like EMI/RFI emitted from the PC is finding its way into your speakers.

I'm betting it is still ground noise - but conducted via the power leads.

 

[popej]

Basic rules:
Turn off all unused inputs in sound control panel. Turn off monitoring for inputs.
Set sound card volume at 100% and use speakers controls for volume.
If you want to use PC volume instead, then set speaker volume as low as possible, while still getting required SPL.

 

[mhardy6647]

I'm betting it is still ground noise - but conducted via the power leads.

Leading one to wonder whether @MKreroo's mains ground is in fact grounded.
I am a trust but verify kind of hominid.
Unless one is absolutely certain that an outlet is wired properly -- it is prudent to check.
It's easy enough to check with a line tester.
Here, for reference, is a US version thereof. A handy thing to have around.

This one even has a GFCI test, which I guess is good.
Mine doesn't -- but then again mine also cost a bit less than this one.

 

[Sokel]

This is a long shot but since it fixed some other user's problem:

I suppose it's a custom built machine,right?
Did you make sure your PSU and the case have the lowest possible resistance?
New,nice looking parts are often not making a good physical contact,one must scratch a small ring around the screw holes sometimes.

You can test that without scratching it with a thick copper cable that will make a good contact (find bare metal) between PSU and PC case.

A long shot,but...

 

[mhardy6647]

You can test that without scratching it with a thick copper cable that will make a good contact (find bare metal) between PSU and PC case.

FWIW, I think that a clip lead would test the hypothesis neatly and easily. If there were a ground issue, the clip lead approach should result in a change in the character of the buzz (e.g., the audible level thereof) and thus provide a route to solve the problem.

I am, in full disclosure:
1) a big fan of clip leads.
2) preternaturally lazy

 

[Sokel]

FWIW, I think that a clip lead would test the hypothesis neatly and easily. If there were a ground issue, the clip lead approach should result in a change in the character of the buzz (e.g., the audible level thereof) and thus provide a route to solve the problem.

I am, in full disclosure:
1) a big fan of clip leads.
2) preternaturally lazy

I would suggest that too but I have seen far too many of them to have resistances up to 20 and 30 Ohm (one had more and one had none )
(talking about new cheap ones from questionable sources)

Thank the gods for Mouser of course with their quality stuff,I never shop elsewhere for more than 10 years now.