PSU makes a strange noise while in fanless/silent mode.

[rtg123]

Hello first time post, I recently installed a new PSU into my computer and noticed a strange noise that happens while I'm playing a game (layers of fear) in fanless/silent mode. The noise quickly goes a way when I press the switch on the back of the PSU and turn the fan on. I've recorded the noise and posted it up on youtube here, try to ignore the noisy case fan above:

Can anyone tell what this noise is? The PSU is a Seasonic focus+ gold 750fx

 

[Liquid Cool]

Welcome to TPU!

Being a "serious" tinnitus sufferer, I'm always on the lookout for strange noises....I know I've heard plenty. The first thing I do in a new build is stick my ear down by a) the chipset, especially on Intel motherboards, and b) the power supply. If both of those check out...I'm usually happy as long as I'm not hearing any high pitch whistling in the air.

So, from listening 5 times...I have to tell you I was having flashbacks to my old floppy drives. Kind of a grinding noise, but I'm not familiar with it. Almost sounds like a hard drive vibrating against bare metal.

Seems kind of odd that this happens when you turn the fan off...instead of on. Thought it might be a fan blade just touching a wire or something. I've had that happen to me once on a Seasonic M12 II 520.

I'm sure some of the other guys will have better ideas....

Best,

Liquid Cool

 

[rtg123]

Yeah I know the feeling, I suffer for tinnitus as well and tend to be extra sensitive with noises; maybe that's how i noticed this sound. Now that you mention it does kind of sound like a floppy or a hardrive... It's worth mentioning that I don't have either installed in this PC. I'll try taking the psu out the pc and checking the fan to make sure nothing is hitting it.

EDIT: I checked, nothing is hitting it the fan as far as i can tell.

 

[eidairaman1]

Whats your complete system specs please

 

[rtg123]

i7 - 5820k (stock speed)
RTX 2080 FE (stock speed)
16GB ram ddr4
Samsung 850 evo 1 TB SSD
Crucial ct256mx100ssd1 256GB SSD
Gigabyte GA-X99-UD4 motherboard
seasonic focus+gold 750w psu

 

[eidairaman1]

Check your motherboard, gpu.

 

[Bill_Bright]

Are you 100% certain the sound is coming from the PSU?

If not, gently rest your finger on your hard drive(s). Can you feel it vibrate with the noise? Gently touch the center hub of your fans and the pitch of the fan noise will change as the rotation speed changes.

Since computer cases are great for transferring sounds and causing hard to pinpoint resonating sounds throughout the case, you might have to unmount the PSU from the case and, with all the cable still connected, flop the PSU outside the case. Then verify the sound is indeed coming from inside the PSU. If it is, then it is likely loose coil or transformer windings or plates. If under warranty, send it back. If not, some strategic application of epoxy cement might stop any vibrations. But I warn you, anything that plugs into the wall can kill! So don't forget to unplug from the wall before even thinking of opening the PSU case.

 

[rtg123]

Yeah I took the PSU out the case and made sure it was the thing that was making the noise, also the noise goes away when I turn on the fan switch on the back of the PSU. The power supply is brand new from amazon so I thankfully don't have to try that epoxy stuff, I think I might send it back and try another one. The thing I'm worried about is if the noise is something serious, like the power supply could malfunction at any minute or something.

 

[eidairaman1]

Yeah I took the PSU out the case and made sure it was the thing that was making the noise, also the noise goes away when I turn on the fan switch on the back of the PSU. The power supply is brand new from amazon so I thankfully don't have to try that epoxy stuff, I think I might send it back and try another one. The thing I'm worried about is if the noise is something serious, like the power supply could malfunction at any minute or something.

Just get an exchange. Someone rmad theirs for fan noise and got one without problems

 

[lexluthermiester]

Could be coil-whine, in which case the only option is to replace the PSU. But even brand new PSU's have some level of it, so if it's not bothering you much, I say just ignore it.

 

[Bill_Bright]

If a PSU is designed to run in silent mode, it should be totally silent when the fan is not spinning. Period! If not totally silent, it is defective and send it back.

If marketed as "Silent", it should be expected to support HTPCs (home theater PCs) which are designed to be totally silent. When you spend a $1000, or many $1000s (or many $10s of 1000s or more!) on a nice home theater setup (and perhaps $1000s more on the home theater room itself), the last thing you need to hear in your home theater is coil-whine or transformer buzz (or even fan noise) when listening to a movie's quiet passage.

The thing I'm worried about is if the noise is something serious, like the power supply could malfunction at any minute or something.

Coil-while and transformer buzz rarely ever, if ever, result in anything serious. In fact, these devices typically keep humming (or buzzing!) along for many years without any problems. But again, if the supply is marketed as a silent supply, there should be no buzz or whine whatsoever. Send it back.

 

[rtg123]

Yeah it should stay silent, I'll probably send and try a new one.

 

[jboydgolfer]

I have this exact power supply sitting in my computer right now, I'll hit the button and see if I hear anything different, but I don't imagine I will as it's always been perfectly silent

Edit
There's absolutely no difference on any of my focus + power supplies (have 3 of them) when I hit that button. It sounds no different in either position