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Unshieleded ATX Power Cables
Posted: 29 Oct 2024, 05:38
by XEM
Hey guys, I am an Electrical and Electronics engineer and I have a deep understanding of EMI.
This summer I made a new setup and it had noisy 3.5mm HDAudio port, I was hearing electrical noise when GPU was pulling some watts.
Then I rerouted HDAudio cable, this time it was near CPU power cable. And whenever i was moving my mouse, i started to hear mouse interference sound.
So my unshielded HDAudio cable was picking up electrical noise and i was hearing that. I've never thought my 12V ATX power cables could act like an antenna, but they were.
I experimented with shielding my HDAudio cable with Aluminum tape, All the noise was gone. Now I am planning to Shield all of my ATX cables (GPU, CPU, 24Pin, sata etc.)
The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise.
I think power draw of CPU slightly changes on each mouse polling, this causes power cables to radiate an EMI field, causing all kinds of problems, USB desync and etc.
Re: Unshieleded ATX Power Cables
Posted: 29 Oct 2024, 06:06
by spkii
It happens too on Consols, PS5 and XBOX, not only computer.
Re: Unshieleded ATX Power Cables
Posted: 31 Oct 2024, 03:24
by Slender
XEM wrote: ↑29 Oct 2024, 05:38
Hey guys, I am an Electrical and Electronics engineer and I have a deep understanding of EMI.
This summer I made a new setup and it had noisy 3.5mm HDAudio port, I was hearing electrical noise when GPU was pulling some watts.
Then I rerouted HDAudio cable, this time it was near CPU power cable. And whenever i was moving my mouse, i started to hear mouse interference sound.
So my unshielded HDAudio cable was picking up electrical noise and i was hearing that. I've never thought my 12V ATX power cables could act like an antenna, but they were.
I experimented with shielding my HDAudio cable with Aluminum tape, All the noise was gone. Now I am planning to Shield all of my ATX cables (GPU, CPU, 24Pin, sata etc.)
The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise.
I think power draw of CPU slightly changes on each mouse polling, this causes power cables to radiate an EMI field, causing all kinds of problems, USB desync and etc.
https://youtu.be/LDEOJtn1Cd8?si=al9rcTb0eANqZN2u
Re: Unshieleded ATX Power Cables
Posted: 31 Oct 2024, 20:16
by themagic
Slender wrote: ↑31 Oct 2024, 03:24
XEM wrote: ↑29 Oct 2024, 05:38
Hey guys, I am an Electrical and Electronics engineer and I have a deep understanding of EMI.
This summer I made a new setup and it had noisy 3.5mm HDAudio port, I was hearing electrical noise when GPU was pulling some watts.
Then I rerouted HDAudio cable, this time it was near CPU power cable. And whenever i was moving my mouse, i started to hear mouse interference sound.
So my unshielded HDAudio cable was picking up electrical noise and i was hearing that. I've never thought my 12V ATX power cables could act like an antenna, but they were.
I experimented with shielding my HDAudio cable with Aluminum tape, All the noise was gone. Now I am planning to Shield all of my ATX cables (GPU, CPU, 24Pin, sata etc.)
The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise.
I think power draw of CPU slightly changes on each mouse polling, this causes power cables to radiate an EMI field, causing all kinds of problems, USB desync and etc.
https://youtu.be/LDEOJtn1Cd8?si=al9rcTb0eANqZN2u
Had exact same and it was low Watt PSU or maybe faulty...the more power the GPU draw..the more worse with sound and it make exact same sound inside/outside headphones while moving mouse and while run some game...
After replace PSU...the problem almost was don't more noticeable...
But if i remember it only happened if using 3,5 input jack back or front...if using USB Audio then the problem don't more exist inside Headphones.
Now the only (similar) electrical sound which I hear is coming direct from GPU...but i read that this has to do with Coil Whine and that this not a bad thing and some GPUs have it more or less today...
https://www.youtube.com/watch?v=zT1sihx ... nel=Dragam
https://www.youtube.com/shorts/rs-vQCXKY6E
here some examples of that sound but here it is not that strong loud noticeable...
Re: Unshieleded ATX Power Cables
Posted: 01 Nov 2024, 21:34
by XEM
themagic wrote: ↑31 Oct 2024, 20:16
Slender wrote: ↑31 Oct 2024, 03:24
XEM wrote: ↑29 Oct 2024, 05:38
Hey guys, I am an Electrical and Electronics engineer and I have a deep understanding of EMI.
This summer I made a new setup and it had noisy 3.5mm HDAudio port, I was hearing electrical noise when GPU was pulling some watts.
Then I rerouted HDAudio cable, this time it was near CPU power cable. And whenever i was moving my mouse, i started to hear mouse interference sound.
So my unshielded HDAudio cable was picking up electrical noise and i was hearing that. I've never thought my 12V ATX power cables could act like an antenna, but they were.
I experimented with shielding my HDAudio cable with Aluminum tape, All the noise was gone. Now I am planning to Shield all of my ATX cables (GPU, CPU, 24Pin, sata etc.)
The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise.
I think power draw of CPU slightly changes on each mouse polling, this causes power cables to radiate an EMI field, causing all kinds of problems, USB desync and etc.
https://youtu.be/LDEOJtn1Cd8?si=al9rcTb0eANqZN2u
Had exact same and it was low Watt PSU or maybe faulty...the more power the GPU draw..the more worse with sound and it make exact same sound inside/outside headphones while moving mouse and while run some game...
After replace PSU...the problem almost was don't more noticeable...
But if i remember it only happened if using 3,5 input jack back or front...if using USB Audio then the problem don't more exist inside Headphones.
Now the only (similar) electrical sound which I hear is coming direct from GPU...but i read that this has to do with Coil Whine and that this not a bad thing and some GPUs have it more or less today...
https://www.youtube.com/watch?v=zT1sihx ... nel=Dragam
https://www.youtube.com/shorts/rs-vQCXKY6E
here some examples of that sound but here it is not that strong loud noticeable...
These examples are just basic coil whine, what i am talking about is EM field created by power cables.
For example, If we shape our atx power cables like a circle, we can make an electromagnet. But it doesn't have to be in that shape, every current carrying conductor creates a magnetic field. That EM field can interfere with other components, especially long PCB traces (naked dram and pcie lanes), USB cables, Noise between GPU and CPU cables...
Re: Unshieleded ATX Power Cables
Posted: 02 Nov 2024, 01:02
by themagic
XEM wrote: ↑01 Nov 2024, 21:34
themagic wrote: ↑31 Oct 2024, 20:16
Slender wrote: ↑31 Oct 2024, 03:24
XEM wrote: ↑29 Oct 2024, 05:38
Hey guys, I am an Electrical and Electronics engineer and I have a deep understanding of EMI.
This summer I made a new setup and it had noisy 3.5mm HDAudio port, I was hearing electrical noise when GPU was pulling some watts.
Then I rerouted HDAudio cable, this time it was near CPU power cable. And whenever i was moving my mouse, i started to hear mouse interference sound.
So my unshielded HDAudio cable was picking up electrical noise and i was hearing that. I've never thought my 12V ATX power cables could act like an antenna, but they were.
I experimented with shielding my HDAudio cable with Aluminum tape, All the noise was gone. Now I am planning to Shield all of my ATX cables (GPU, CPU, 24Pin, sata etc.)
The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise.
I think power draw of CPU slightly changes on each mouse polling, this causes power cables to radiate an EMI field, causing all kinds of problems, USB desync and etc.
https://youtu.be/LDEOJtn1Cd8?si=al9rcTb0eANqZN2u
Had exact same and it was low Watt PSU or maybe faulty...the more power the GPU draw..the more worse with sound and it make exact same sound inside/outside headphones while moving mouse and while run some game...
After replace PSU...the problem almost was don't more noticeable...
But if i remember it only happened if using 3,5 input jack back or front...if using USB Audio then the problem don't more exist inside Headphones.
Now the only (similar) electrical sound which I hear is coming direct from GPU...but i read that this has to do with Coil Whine and that this not a bad thing and some GPUs have it more or less today...
https://www.youtube.com/watch?v=zT1sihx ... nel=Dragam
https://www.youtube.com/shorts/rs-vQCXKY6E
here some examples of that sound but here it is not that strong loud noticeable...
These examples are just basic coil whine, what i am talking about is EM field created by power cables.
For example, If we shape our atx power cables like a circle, we can make an electromagnet. But it doesn't have to be in that shape, every current carrying conductor creates a magnetic field. That EM field can interfere with other components, especially long PCB traces (naked dram and pcie lanes), USB cables, Noise between GPU and CPU cables...
So the example from Slender is not your case ?
I had only these sounds but as I said after replacing PSU or get new PC case with those HDaudio cable inside...i stop to hear these sounds and everything was fine again...
Re: Unshieleded ATX Power Cables
Posted: 02 Nov 2024, 13:27
by themagic
https://youtu.be/LDEOJtn1Cd8?si=al9rcTb0eANqZN2u
idk i had same issue with be quit 550 watt (if remember right) and the cables was shielded from that psu i think...they was not naked if remeber right and HDaudio cable too...
after i change to 700watt (be quiet pure power 11) then the issue disappear as in example video by slender (where i had exact same exprience with psu and could even hear this sound in my headhones and by my mouse movements) and even my gpu whine coil got lower on sound when under high power draw after switch to this 700 watt model...
@XEM
"The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise."
can you record these sounds and upload here ? sounds it like white static noise from an old TV ? and how about USB audio ? you hear any inteference (white noise) sounds on high volume ?
Re: Unshieleded ATX Power Cables
Posted: 02 Nov 2024, 20:29
by Slender
themagic wrote: ↑02 Nov 2024, 13:27
https://youtu.be/LDEOJtn1Cd8?si=al9rcTb0eANqZN2u
idk i had same issue with be quit 550 watt (if remember right) and the cables was shielded from that psu i think...they was not naked if remeber right and HDaudio cable too...
after i change to 700watt (be quiet pure power 11) then the issue disappear as in example video by slender (where i had exact same exprience with psu and could even hear this sound in my headhones and by my mouse movements) and even my gpu whine coil got lower on sound when under high power draw after switch to this 700 watt model...
@XEM
"The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise."
can you record these sounds and upload here ? sounds it like white static noise from an old TV ? and how about USB audio ? you hear any inteference (white noise) sounds on high volume ?
same. im bought new psu 850w (superflower platinum) and usb dac and that sound is dissapear in my hp. But that psu give 500-600mv when start, and ~1500mv when fully connected.
my gf 650w have that weird sound but it ads only 50-100mv when start with full connected!
Re: Unshieleded ATX Power Cables
Posted: 05 Nov 2024, 03:50
by amorou
XEM wrote: ↑29 Oct 2024, 05:38
Hey guys, I am an Electrical and Electronics engineer and I have a deep understanding of EMI.
This summer I made a new setup and it had noisy 3.5mm HDAudio port, I was hearing electrical noise when GPU was pulling some watts.
Then I rerouted HDAudio cable, this time it was near CPU power cable. And whenever i was moving my mouse, i started to hear mouse interference sound.
So my unshielded HDAudio cable was picking up electrical noise and i was hearing that. I've never thought my 12V ATX power cables could act like an antenna, but they were.
I experimented with shielding my HDAudio cable with Aluminum tape, All the noise was gone. Now I am planning to Shield all of my ATX cables (GPU, CPU, 24Pin, sata etc.)
The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise.
I think power draw of CPU slightly changes on each mouse polling, this causes power cables to radiate an EMI field, causing all kinds of problems, USB desync and etc.
Mouse inputs has very high priority for interrupting cpu , and polling use lots of cpu power, you are hearing that .
Any cpu demanding task will make these noises , prolly they wont cause interference with operation of perhipals
Re: Unshieleded ATX Power Cables
Posted: 07 Nov 2024, 22:02
by XEM
Slender wrote: ↑02 Nov 2024, 20:29
themagic wrote: ↑02 Nov 2024, 13:27
https://youtu.be/LDEOJtn1Cd8?si=al9rcTb0eANqZN2u
idk i had same issue with be quit 550 watt (if remember right) and the cables was shielded from that psu i think...they was not naked if remeber right and HDaudio cable too...
after i change to 700watt (be quiet pure power 11) then the issue disappear as in example video by slender (where i had exact same exprience with psu and could even hear this sound in my headhones and by my mouse movements) and even my gpu whine coil got lower on sound when under high power draw after switch to this 700 watt model...
@XEM
"The weird part was I was hearing my mouse's polling rate through audio port. 1KHz exactly, when I set my polling rate to 125Hz, it was a different noise."
can you record these sounds and upload here ? sounds it like white static noise from an old TV ? and how about USB audio ? you hear any inteference (white noise) sounds on high volume ?
same. im bought new psu 850w (superflower platinum) and usb dac and that sound is dissapear in my hp. But that psu give 500-600mv when start, and ~1500mv when fully connected.
my gf 650w have that weird sound but it ads only 50-100mv when start with full connected!
I am using Aerocool P7 850W Platinum PSU. I will try to record the noise but i already solved the problem by shielding HDAudio cable with aluminum tape. I will unwrap the tape for the sake of experiment. On my oscilloscope, 12V rail had ~20mv peak to peak ripple
at ~700 watts and 6mv PP Ripple on idle. 500mv ripple seems too much, I think that PSU is broken.