[SOLVED] What is this sound coming from my power supply?

Hallahawk665

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I keep hearing this sound from my power supply. The weird thing is that it goes away when it's under load (such as when playing a GPU or CPU intensive game) but it gets pretty damn loud when the PC is idling or doing simple tasks. It sounds alot like a short circuit sound but the PC has been working just fine so I have no idea what is happening. The PSU in question is a Seasonic S12III 650W. Here is a video of the sound (you may need to turn up your volume):
View: https://www.youtube.com/watch?v=m3EmeGkOMNs
 
Solution
So your saying the noise is the sound of the PWM activating as the mosfet is switching/ filtering the current and or voltage?

No. I said the noise could be coming from the PFC coil. MOSFETs don't make audible noise, but create a lot of electrical noise.

The noise kind of sounds like a capacitor (a mosfet can sometimes be a capacitor?)

No. Only caps I've heard make noises are those in the process of venting and some X capacitors because the film can resonate with noise on the mains.

which as you will know can store a charge during the AC wavelength when unused then use the stored power when the sine wave supplies less than your appliances prescribed voltage.

Yes and no. The filtering caps filter noise...
Many times it's not easy to hear in a recording what you are hearing live....as the quality is different etc. However...as a general rule....if a PSU starts making a new noise....and I can't specifically determine what it is....I definitely would consider replacing it....as something has changed...and nothing should change.
....and what will this "change" cause to happen?
We don't know.
 
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Garbage PSU ("tier D" in this list: https://forums.tomshardware.com/threads/psu-tier-list-psucultists.3624094/)

Made by RSY. Dual mag amp secondary. It uses a Monolith HR1000A PWM IC to support burst mode at low loads, but instead of designing the PSU around the goal like what Corsair and Cooler Master did with their "bust mode" PSUs, Seasonic's engineers just "dropped in" a pin for pin compatible IC to replace the previous LLC controller.

What does all this mean:
RSY: Low tier manufacturer
Dual mag amp: Output rails are not independently regulated
Bust mode: PWM controller switches from LLC to a "burst mode" to improve low load efficiency. Basically, it switches the MOSFETs from the standard on/off switching to "bursts" of on/off, on/off, etc. This is what is making the noise since the primary part of the platform was not originally designed for this IC.
 

Hallahawk665

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Jun 17, 2020
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Garbage PSU ("tier D" in this list: https://forums.tomshardware.com/threads/psu-tier-list-psucultists.3624094/)

Made by RSY. Dual mag amp secondary. It uses a Monolith HR1000A PWM IC to support burst mode at low loads, but instead of designing the PSU around the goal like what Corsair and Cooler Master did with their "bust mode" PSUs, Seasonic's engineers just "dropped in" a pin for pin compatible IC to replace the previous LLC controller.

What does all this mean:
RSY: Low tier manufacturer
Dual mag amp: Output rails are not independently regulated
Bust mode: PWM controller switches from LLC to a "burst mode" to improve low load efficiency. Basically, it switches the MOSFETs from the standard on/off switching to "bursts" of on/off, on/off, etc. This is what is making the noise since the primary part of the platform was not originally designed for this IC.
Can this harm the PSU or my components? I didn't hear it before, it just started today so if it's caused by the mosfets then why didn't it always make this sound? I'll replace it anyway but I'm just curious.
 
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Can this harm the PSU or my components? I didn't hear it before, it just started today so if it's caused by the mosfets then why didn't it always make this sound?

The sound isn't made by the MOSFETs. It's caused by the switching of the MOSFETs and the sound is the current pulsing through the magnetics (probably the inductor coil). They probably covered a bunch of components with caulk and it's fallen off or dried up or something.
 

Hallahawk665

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The sound isn't made by the MOSFETs. It's caused by the switching of the MOSFETs and the sound is the current pulsing through the magnetics (probably the inductor coil). They probably covered a bunch of components with caulk and it's fallen off or dried up or something.
Is there any way this can damage my components? Because I still need to use the PC until I get a new PSU
 

Windows22

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Garbage PSU ("tier D" in this list: https://forums.tomshardware.com/threads/psu-tier-list-psucultists.3624094/)

Made by RSY. Dual mag amp secondary. It uses a Monolith HR1000A PWM IC to support burst mode at low loads, but instead of designing the PSU around the goal like what Corsair and Cooler Master did with their "bust mode" PSUs, Seasonic's engineers just "dropped in" a pin for pin compatible IC to replace the previous LLC controller.

What does all this mean:
RSY: Low tier manufacturer
Dual mag amp: Output rails are not independently regulated
Bust mode: PWM controller switches from LLC to a "burst mode" to improve low load efficiency. Basically, it switches the MOSFETs from the standard on/off switching to "bursts" of on/off, on/off, etc. This is what is making the noise since the primary part of the platform was not originally designed for this IC.
Makes sense.
 

Hallahawk665

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Try this: In your BIOS, under power management, disable ErP. This should increase your idle load and hopefully take the PSU out of burst mode.
I looked in the bios and ErP is already disabled. Is the PSU damaging anything or itself when it enters that low power mode that causes the sound or is it just the sound and that's it?
 

ClapTrapper

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Many times it's not easy to hear in a recording what you are hearing live....as the quality is different etc. However...as a general rule....if a PSU starts making a new noise....and I can't specifically determine what it is....I definitely would consider replacing it....as something has changed...and nothing should change.
....and what will this "change" cause to happen?
We don't know.
I couldn't hear a thing either.
 
I think it's still under warranty but I think it's better to just buy a new one if it really is this bad

No. Warranty just gets you the same PSU that will do the same thing. Sometimes, stores give you 30 or 90 day or whatever return policies. If you're past that, replace it and keep the PSU for another project where the noise won't be a bother. Maybe a "retro build" or something.
 

Hallahawk665

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No. Warranty just gets you the same PSU that will do the same thing. Sometimes, stores give you 30 or 90 day or whatever return policies. If you're past that, replace it and keep the PSU for another project where the noise won't be a bother. Maybe a "retro build" or something.
Alright, well it's out of the return window so I'll just get a new one
 

Hallahawk665

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No. Warranty just gets you the same PSU that will do the same thing. Sometimes, stores give you 30 or 90 day or whatever return policies. If you're past that, replace it and keep the PSU for another project where the noise won't be a bother. Maybe a "retro build" or something.
HEY I think I just found the real cause of the noise. Some electricians came and worked at our house and they had to remove some broken regulation/safety mechanism but they didn't replace it so now there is no safety circuit or whatever. Ever since then, the lightbulbs flicker every once in a while. This time, I heard the noise again pretty loudly, and my internet stopped working too at the same time. The red power light on the power strip was flickering, and the lightbulbs were flickering really badly too. I even heard the noise coming from the PSU when the PC was shut off but the power strip was still on. I turned off the power strip and the noise stopped, but the lights in the house kept flickering so I don't think the problem is caused by the PSU messing up the home's electrical system. Plus the lightbulbs flicker every now and then even when the PC is completely off. Could this be the real cause of the sound? Especially since I don't always hear it when it's idle, only sometimes.
EDIT: But I am 100% sure that I ONLY ever heard the noise when the PC is not doing much, so could the noise be a combination of the problem you mentioned and the home's crappy electrical work?
EDIT2: I also heard some popping/crackling noises in my headphones for a bit, and this was while the psu WASN'T making any sounds.
 
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HEY I think I just found the real cause of the noise. Some electricians came and worked at our house and they had to remove some broken regulation/safety mechanism but they didn't replace it so now there is no safety circuit or whatever. Ever since then, the lightbulbs flicker every once in a while. This time, I heard the noise again pretty loudly, and my internet stopped working too at the same time. The red power light on the power strip was flickering, and the lightbulbs were flickering really badly too. I even heard the noise coming from the PSU when the PC was shut off but the power strip was still on. I turned off the power strip and the noise stopped, but the lights in the house kept flickering so I don't think the problem is caused by the PSU messing up the home's electrical system. Plus the lightbulbs flicker every now and then even when the PC is completely off. Could this be the real cause of the sound? Especially since I don't always hear it when it's idle, only sometimes.
EDIT: But I am 100% sure that I ONLY ever heard the noise when the PC is not doing much, so could the noise be a combination of the problem you mentioned and the home's crappy electrical work?
EDIT2: I also heard some popping/crackling noises in my headphones for a bit, and this was while the psu WASN'T making any sounds.

If you think it's your mains, take the PC to another building, like a friend's house, etc. and try it there.

But it is normal for that particular PSU to make a buzz buzz at low loads (< 10%).
 

sgnz

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HEY I think I just found the real cause of the noise. Some electricians came and worked at our house and they had to remove some broken regulation/safety mechanism but they didn't replace it so now there is no safety circuit or whatever. Ever since then, the lightbulbs flicker every once in a while. This time, I heard the noise again pretty loudly, and my internet stopped working too at the same time. The red power light on the power strip was flickering, and the lightbulbs were flickering really badly too. I even heard the noise coming from the PSU when the PC was shut off but the power strip was still on. I turned off the power strip and the noise stopped, but the lights in the house kept flickering so I don't think the problem is caused by the PSU messing up the home's electrical system. Plus the lightbulbs flicker every now and then even when the PC is completely off. Could this be the real cause of the sound? Especially since I don't always hear it when it's idle, only sometimes.
EDIT: But I am 100% sure that I ONLY ever heard the noise when the PC is not doing much, so could the noise be a combination of the problem you mentioned and the home's crappy electrical work?
EDIT2: I also heard some popping/crackling noises in my headphones for a bit, and this was while the psu WASN'T making any sounds.

First off did this only occur after the electrical work was completed? Can you explain more on what the electricians did? Im an electrician albeit im from New Zealand so our rules and regulations not to mention our power distribution network is potentially quite different. We use no nuclear. Mainly hydroelectric / and wind but some fossil fuels :/ If your having issues since electrical work has been carried out im pretty positive its something they have done negligently!
Just a wild guess are you from the states?
What safety mechanisms are you talking about?