PSU coilwhines while PC turned off?

[Wauthar]

Hey all,

 

I have a strange problem: when I turn my computer off my PSU (and I am sure it is the PSU) emits a very high pitched noise, almost like a low-volume coil whine.

When my PC is turned on, there is no problem. But as soon the fans stop spinning (etc.) it starts.

Does someone know this problem and how to solve it? It does go away if I flip the switch at the back, but that shouldn't be necessary.

 

It would be great if someone could help me.

 

- Wauthar

[Owen]

It could be the fan slowing down/ stopping? Wait a a minute or two after you turn your computer off and see if it still makes that noise.

[Wauthar]

It could be the fan slowing down/ stopping? Wait a a minute or two after you turn your computer off and see if it still makes that noise.

Oh it does. It just keeps on whining.

[BroKenFingers]

I would think it is your PSU. A PSU is in effect always on..they pass a current to your MB or USB charge ports, even with the system "powered down". Turning the switch at the back off should have the same effect as pulling the plug.The coil whine you hear is the sound made by electromagnetic coils under power..and it only stops when you turn the switch off at the back or pull the plug. You just happen to hear it because the rest of the system noise is gone...

Wikipedia says this :  http://en.wikipedia.org/wiki/Coil_noise

 

 

"The amount of coil noise in a device will often seem to increase as the devices age. This can be due to many factors, but is often due to the degradation of the damping materials in the circuit. As an example, a layer of glue is often added atop coils in televisions. Over the years, this glue degrades due to age and due to the years of vibration it has been subjected to. As a result, the coil is able to move more as it vibrates, and the sound level increases."

 

Might be time for a new PSU..? Good Luck..let us know what happens.. :) 

[Wauthar]

I would think it is your PSU. A PSU is in effect always on..they pass a current to your MB or USB charge ports, even with the system "powered down". Turning the switch at the back off should have the same effect as pulling the plug.The coil whine you hear is the sound made by electromagnetic coils under power..and it only stops when you turn the switch off at the back or pull the plug. You just happen to hear it because the rest of the system noise is gone...

Wikipedia says this :  http://en.wikipedia.org/wiki/Coil_noise

 

 

"The amount of coil noise in a device will often seem to increase as the devices age. This can be due to many factors, but is often due to the degradation of the damping materials in the circuit. As an example, a layer of glue is often added atop coils in televisions. Over the years, this glue degrades due to age and due to the years of vibration it has been subjected to. As a result, the coil is able to move more as it vibrates, and the sound level increases."

 

Might be time for a new PSU..? Good Luck..let us know what happens.. :) 

Thank you for your answer.

Does this happen to all electric components during their lifespan? I think it is strange this is happening to my PSU, since it is just over a year old. (I built my rig in March 2012)

I kinda don't want to buy a new PSU, so this one has to hold a bit longer. Maybe I will switch it off when not in use.

[BroKenFingers]

Some will and some others will not...Keep an eye on your system(clean the dust away) ..and if you hear any gross changes in the noise , act accordingly . Powering off the system is a good idea. Good luck.