Question Unknown on-off buzzing noise coming from PC

[Cory Compton]

I'm getting random buzzing sounds coming from my PC. It goes in and out at random and doesn't seem to be affected when my system is under load (such as heavy gaming). I have replaced both my power supply and case fans as they seemed like the most obvious culprits, but the noise has persisted. I've also tested each case fan individually by ramping each fan to full speed in BIOS, so I know for sure that they're not the cause. Did I just-so-happen to get 2 faulty power supplies, or could something else be causing the issue? And should I be worried about the noise if I can't fix it? Everything seems to be in good working order minus the random buzzing noises, but from what I've read in other forums the buzzing sound could indicate a failing power supply (even though mine is brand new?). Also noticed that the buzzing noise "changes" when doing certain things on the monitor such as scrolling through a web page.

Audio samples:

https://imgur.com/a/qoOeXUC

View: https://imgur.com/a/qoOeXUC

https://imgur.com/a/ISJQGVx

View: https://imgur.com/a/ISJQGVx


My specs:

Case: Montech Air 100 ARGB
PSU: Cooler Master MasterWatt 750 (both old and new replacement)
GPU: Gigabyte Eagle AMD RX 6650XT
CPU: Intel Core i3-12100F
Motherboard: ASRock B660M PRO RS LGA 1700 mATX
RAM: XPG Z1 DDR4 3200MHz (2x8GB)

 

[Lutfij]

The sound seems like there's a stray cable brushing up against the fan blades...maybe even something as small as a ziptie. It might also be that the fans are subpar in quality and they noise is originating from the fan's motor housing. Might want to roll up a sheet of A4 paper and hold one end to your ear while the other is used to probe for the source of the noise. You're going to have to take the side panels off for this test, mind you.

PSU: Cooler Master MasterWatt 750 (both old and new replacement)

Cooler Master MasterWatt 750 Semi-fanless Modular 80 Plus Bronze Certified ATX PSU

The MasterWatt 750 is a 80 Plus Bronze Power supply with an innovative semi-fanless mode. Under 15% load, the MasterWatt fan remains idle, offering zero dBA. When demand for power increases, a gradual fan curve provides measured cooling with little to no noise at any output level. Dual forward /...

www.coolermaster.com

is this the unit you're working with?

How are you cooling the processor?

 

[Cory Compton]

The sound seems like there's a stray cable brushing up against the fan blades...maybe even something as small as a ziptie. It might also be that the fans are subpar in quality and they noise is originating from the fan's motor housing. Might want to roll up a sheet of A4 paper and hold one end to your ear while the other is used to probe for the source of the noise. You're going to have to take the side panels off for this test, mind you.

PSU: Cooler Master MasterWatt 750 (both old and new replacement)

Cooler Master MasterWatt 750 Semi-fanless Modular 80 Plus Bronze Certified ATX PSU

The MasterWatt 750 is a 80 Plus Bronze Power supply with an innovative semi-fanless mode. Under 15% load, the MasterWatt fan remains idle, offering zero dBA. When demand for power increases, a gradual fan curve provides measured cooling with little to no noise at any output level. Dual forward /...

www.coolermaster.com

is this the unit you're working with?

How are you cooling the processor?

Yes that's the correct PSU. I double checked all the cabling and connections and didn't find anything brushing up against the fans, though admittedly the fans I'm using are cheap Thermalright ARGB fans so it's possible their motors are junk. But you'd think the buzzing noise would've been more noticeable after running them at full speed during my testing?

This is what I'm using to cool the CPU: ID-COOLING SE-214-XT ARGB White... https://www.amazon.com/dp/B09Q7XVZ2V?ref=ppx_pop_mob_ap_share

 

[SkyNetRising]

I've also tested each case fan individually by ramping each fan to full speed in BIOS, so I know for sure that they're not the cause.

That wouldn't let you find, if multiple fans are making the same noise.

Disconnect your fans (one at the time) to find which one is causing the noise.
If multiple fans are causing same noise, then you'd have to disconnect them all.

 

[Cory Compton]

I followed the advice of disconnecting the case fans but I'm still getting the buzzing noise. In the video below I have all the fans in the case (including the CPU cooler fan) disconnected, and the GPU fans were also not running since it uses a zero RPM mode while not under load. Not sure how noticeable it is in the video, but the buzzing sound 'reacts' and changes somewhat when I'm scrolling with the mouse.

Honestly clueless at this point what's causing it. All my connections are tight and secure, and there are no moving parts in my case besides the PSU (which I just replaced). The PC uses a single m.2 Nvme SSD so there are also no spinning hard drives.

Thoughts?

https://imgur.com/a/IoSO4tT

View: https://imgur.com/a/IoSO4tT

 

[SkyNetRising]

the buzzing sound 'reacts' and changes somewhat when I'm scrolling with the mouse.
Honestly clueless at this point what's causing it.

Could that sound be coming from speakers?
Try disconnecting them.

 

[Cory Compton]

Could that sound be coming from speakers?
Try disconnecting them.

I've already tried turning off and disconnecting each of my peripherals (including speakers) without any luck. Plus the noise is louder when I remove the side panel and move my head closer to the case so it's definitely coming from something within the PC.