[SOLVED] Brand new Corsair RM750x has "reverse" coil whine

kimonji

Honorable
Apr 8, 2015
14
0
10,520
Hi,
I got a new RM750x for my new PC build (9700k+2080S). I noticed a very faint buzzing sound from the PSU when my PC is idling or browsing the internet that is only audible if I place my ear physically adjacent to the PSU. This sound actually diminishes as I put my PC under load. The heavier the load the quieter it gets. And when I relieve my PC back to idle, the faint buzz resumes. I am sure it is the PSU not anything else, even under load.

So my question is while this may not be "normal", the sound only bothers me when I'm paranoid about it and put my ear next to the PSU to listen lol. Would this not be harmful to my PC down the road? I really prefer not to return it because wiring/re-wiring PSU is such a pain. I have 30 days to return this thing so I'll observe it for a few days unless I'm told that this is dangerous and I need to return it now.
 
Solution
That's NOT ''Coil Whine''!! A ''buzz'' is from the 50/60Hz AC from the wall outlet. It's normal in that it can cause some components to resonate. That is why manufacturers put a glue-like or silicone substance on and around some components on the circuit boards. It keeps the components from coming loose during shipping, and also serves as a noise dampener for some components as well. Flourescent Lights have a nasty habit of exhibiting this noise.

Check all your case, PCI Cover Plate(s) and PSU mount screws are tight, that all your case panels fit tight and that your motherboard, hard drives and any other components inside the case are tight (*DO NOT OVERTIGHTEN motherboard screws - ''snug'' is fine!)

Also, if you have an...

ChevetteSCx

Reputable
Sep 5, 2019
90
7
4,565
That's NOT ''Coil Whine''!! A ''buzz'' is from the 50/60Hz AC from the wall outlet. It's normal in that it can cause some components to resonate. That is why manufacturers put a glue-like or silicone substance on and around some components on the circuit boards. It keeps the components from coming loose during shipping, and also serves as a noise dampener for some components as well. Flourescent Lights have a nasty habit of exhibiting this noise.

Check all your case, PCI Cover Plate(s) and PSU mount screws are tight, that all your case panels fit tight and that your motherboard, hard drives and any other components inside the case are tight (*DO NOT OVERTIGHTEN motherboard screws - ''snug'' is fine!)

Also, if you have an LCD Monitor with a 14VDC (Samsung) or 19VDC (LG, Acer) brick power supply, when you put your ear to that, it should buzz lightly, too.
 
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Solution
Hi,
I got a new RM750x for my new PC build (9700k+2080S). I noticed a very faint buzzing sound from the PSU when my PC is idling or browsing the internet that is only audible if I place my ear physically adjacent to the PSU. This sound actually diminishes as I put my PC under load. The heavier the load the quieter it gets. And when I relieve my PC back to idle, the faint buzz resumes. I am sure it is the PSU not anything else, even under load.

So my question is while this may not be "normal", the sound only bothers me when I'm paranoid about it and put my ear next to the PSU to listen lol. Would this not be harmful to my PC down the road? I really prefer not to return it because wiring/re-wiring PSU is such a pain. I have 30 days to return this thing so I'll observe it for a few days unless I'm told that this is dangerous and I need to return it now.
"only audible if I place my ear physically adjacent to the PSU. "
If it's that quiet I think it's normal.
I have 2 RM series PSUs at home including a 750 watt.
I've never had an issue with them.
I'll give a listen when I get home.
 

kimonji

Honorable
Apr 8, 2015
14
0
10,520
Ok, thanks guys! And yes my LCD monitor's power brick does buzz a little when I listen carefully to it. I'm relieved to hear that it's normal. Hopefully it stays that way.