I highly recommend you RMA the unit asap, what your probably hearing is called coil squeal. Sometimes the caps while charging and discharging noises but it is not normal for a brand new power supply that is not even pushed to its max capacity. Considering it occurs even when switched off urges me to tell you to rip that thing out of your computer right now before something bad happens to one of the components or that power supply bursts into flames or tons of smokes starts to show up
You can try to buy a power strip but the noise is definitely because of the coil squeal, technically its okay to hear some squealing noise when its on and near full power usage but you claim when its off its making that noise leads me to believe you have defective caps. Of course even though your computer is off your computer still uses electricity, this is called phantom load, your computer still needs electricity in it to respond to your touching of the power button. As a suggestion let me know if you hear the noise when you turn off the power strip itself (should have a red switch on the power strip to turn it off from where I am from).
Also this is a common issue for low end power supplies including cooler master, they are made so cheaply that they fail real easily and die out within a year or two. This does not apply if you have one of those high end cooler master power supplies. Technically from now on I suggest buying from well known brands such as Antec, Corsair, XFX, Seasonic, Pc power and cooling, Enermax, Kingwin and maybe Raidmax. Point is these brands may not be all available to you based on your geographic area. If your in North America then you will find all these brands. What all these brands have in common is that they use quality parts in the power supplies and they ACCURATELY label their power supplies and so it provides just about the same amount of watts labelled.
Ok if it does stop buzzing when you unplug the power cord from it then your culprit is the power supply. Anyways what is the exact model of the power supply?
Even the best of power supplies can have issues but its those good companies that allow you to RMA it for another product. If you power supply is actually bronze rated and modular I presume you just got that one lemon out of an entire branch which is unfortunate.
Okay that power supply is a really good one since it is one of Cooler Master's high end ones, what I mean by high end refers to the quality of their power supply and the watts it actually provides. Is there by any change you know how much amps your using on the 12v rail? Once again if your near 100% load your experiencing noise from your coils which is okay to hear but since it occurs even when its off that leads to a defective power supply.
Sounds like a coil whine. Yea I would recommend like others have mentioned to return the power supply. Also I would suggest perhaps going with a different power supply. The one you have is good I just have a easier time buying from a seasonic based psu maker they tend to have more favorable reviews/results.
+1^ if you can when you get the RMA perhaps sell it? Use the money to buy a quality power supply as I stated above " Antec, Corsair, XFX, Seasonic, Pc power and cooling, Enermax, Kingwin and maybe Raidmax." Though I highly doubt the chances of you getting a defective power supply twice in a row.
I would recommend it on the new replacement power supply he gets but not on the current one, wouldn't surprise me if he did stress out his current power supply and heap loads of smoke comes out or even possible fire or sparks occur
haha ya you are probably right I would get a flat refund if you could through the rma process and then go for the corsair but if you can't do that stress test the cooler master one just to be sure the one you would receive that is.
The voltage on the 12v rail is fine, you have a problem if its below 12v. I guess there you should try another wall socket. Generally, the power supply is still giving off minimal power to the motherboard (phantom load) so the power button responds but it should not be buzzing. Also try taking your power supply out and re-mounting it and screwing it in tight (but not to the point you strip the screws). The power supply should not be wiggling.
I highly recommend you RMA the unit asap, what your probably hearing is called coil squeal. Sometimes the caps while charging and discharging noises but it is not normal for a brand new power supply that is not even pushed to its max capacity.
"Coil whine" comes from inductor/transformer windings or a loose transformer core, not capacitors. Depending on the exact cause, it can happen at any load level and may not necessarily be a problem aside from the annoyance factor.
Since the noise happens even when the PC is off, the noise must be coming from the 5VSB supply.
I have an 8 years old PSU with 'coil whine' while in standby. The whine's pitch changes in sync with the blinking standby LED. Aside from the slight annoyance, I haven't had any (other) problems with it.