Weird sound on my RM750x (2018)

[Minos]

Hello,

I just built my new pc and it is working fine (but I didn't use it yet in games). However when my pc is turned off (but still alimented) or asleep, I can hear a weird continious sound coming from my PSU RM750x (2018).. This sound disapear when I disconnect the 24pin cable from de PSU or when I stop alimenting the psu.

 

This is the kind of sound i can hear :

 

I am worried that the psu can damage other of my components, but I am still a rookie.. What do you think ?

 

System:

i7-10700F

MAG Z490 TOMAHAWK

GeForce RTX3070 VENTUS 3X OC

Corsair 32 Go (2x16) DDR4-3000MHz Vengeance

be quiet! Dark Rock PRO 4

Corsair Force MP510 V2 960 Go

Samsung Série 870 QVO 1 To

SanDisk SSD PLUS TLC 2 To

5x140mm fans

3x120mm fans

[Corsair Elito]

Hi Mino's

 

That is coil whine, it AC power converted to DC power,

 

https://www.corsair.com/ww/ru/blog/coil-whine

[Vegan]

I found that long ago using filter capacitors removed the noise from the AC side efficiently with linear designs as well as with operational amp designs

 

surprised that these are not that common anymore, capacitors are not expensive

 

this is related to power factor which is an advanced topic in electrical engineering

Edited February 8, 2021 by Vegan

[LeDoyen]

the noise can come from something else in the electrical crcuit where the PSU is plugged, like some phone charger, neon lights, anything.

If the PC is on a power strip, it would be a good test to unplug things one by one and see if the PSU keeps making noise. Sometimes it's one pesky badly filtered device that introduces noise in the mains and it messes with the power supply.

[Minos]

Hello ! Thank you for your responses.

 

Hi Mino's

 

That is coil whine, it AC power converted to DC power,

 

https://www.corsair.com/ww/ru/blog/coil-whine

 

I didn't know that a coil whine could appear when the computer was turned off. I'm a little confused, some people say it's perfectly normal and not to worry, others talk about RMA .. Sorry for my dumb questions but .. Is it sure that it can't damage any components of my computer? I don't really want to change my new PSU, but if it necessary I will do it..

 

the noise can come from something else in the electrical crcuit where the PSU is plugged, like some phone charger, neon lights, anything.

If the PC is on a power strip, it would be a good test to unplug things one by one and see if the PSU keeps making noise. Sometimes it's one pesky badly filtered device that introduces noise in the mains and it messes with the power supply.

 

Yes I heard something like that, so I already tried to put my computer on a single wall outlet, but the sound was still there.

 

By the way, I was able to minimize the sound by enabling the erp mode in my bios. The noise is now extremely small, on the other hand I didn't find a solution when the pc is in standby (I can easily hear the noise) .. If someone has a solution for me I am interested ..

[LeDoyen]

ErrP is extremely low power mode in shutdown state (less than 1W) so, maybe it's the 5VSB that is creating coil whine and not the PFC circuit..

the 5V standby supply is constantly running even when the PC is off. it's needed in order to run basic stuff like... your case's power button amongst other things.

So there's always some voltage conversion going on.

 

In itself it's not a defect. Coil whine doesn't hurt anything, but becasue it can be annoying, people RMA their PSU to get one with less or no whine when it happens.

Same goes for videocards. some are more noisy than others, and when stock wasn't an issue, people would often RMA their card to get a more silent one, if the manufacturer accepted that (not all did since again, whine isn't a defect in itself).

[Vegan]

One of the more expensive power bars usually sold to TV crowd have better filtering and other protection which can help with backwards power factor

 

if the power gets out of phase such as when electric motors start it can be bad for a wide area while it starts up