Strange PSU buzzing with 2 PCs.

[McSkops]

I have an Corsair HX 750 that makes no weird sounds at all normally. However, my Uncle's PC is some really junk Fujitsu that makes some bad buzzing noises.

Issue is: as soon as my Uncle turns on his PC, my PSU will mimic the same buzzing noises as his PC. Albeit not as awful, but same patterns.

This doesn't affect performance of anything, but I'd like an explanation and whether it's bad for any components. Is this something to do with power in the house? We aren't connected to the same extension or wall socket either.

And turning MY PC off does not stop the buzzing in his PC.

 

[asoroka]

I suspect that the noise is coming from the power supply transformer.

I assume your PC and your uncles are in the same house. How close are they?

If you want to experiment, you can take his PC power supply out and put your power supply in its place.
Does it still make the noise?

 

[McSkops]

I suspect that the noise is coming from the power supply transformer.

I assume your PC and your uncles are in the same house. How close are they?

If you want to experiment, you can take his PC power supply out and put your power supply in its place.
Does it still make the noise?

Both PCs are in the living room 5 feet away from each other. I don't think I'm able to hook up my PSU to such an ancient office PC, and frankly, it's not worth the hassle to do so when we could just get a new cheap modern PC to replace it.

I'm just extremely curious why the noise appears in my PC as soon as he turns his PC on. Can't find anything on google because it sounds ridiculous.

 

[asoroka]

most likely electro magnetic interference. The old PC is either acting as a low frequency radio transmitter (unshielded power supply transformer) and your Power supply is picking it up.

The noise will most likely be due to the transformer core (or coils moving in sync with the mains frequency, 60Hz in USA, 50Hz for most other parts of the world.

The further away you move the two pcs, the less cross noise you will get.

That would be my guess, try changing the separation to see if it makes a difference

 

[smorizio]

quick test. plug in two lamps where the pc are plugged in. have the pc off and the surge supressors off. go to the fuse box turn off the breaker for that room. if both lamps are out the both pc are on the same breaker and your getting feedback from a bad ground. if he house is a few years old have a licensed electrtion check that the wires are tight in the fuse box. al wires need to be tighten and have anti rust placed on them every 3-4 years. have him also check that the outlets in that room have good ground. on the old pc take it outside make sure it not full of dust that making bridges inside the pc. same for any bug in the pc. bugs love the wires inside power supplys. and a big bug can make a jumper in a power supply. with the pc with the issue check to see if the power supply under warranty. some units have long warranty. if it is rma it. if it out look at one of the seasonic 620w units there not a lot and there a good unit. a lot of times the old power supplys will have leaking/bad caps.