Cooler Master Real Power Pro 750 makes a weird hum/whine sometimes

[9nines]

I have a new PC build that is a month old. It has an Asus P5Q Delux P45 motherboard, E8400 CPU (not overclocked yet), 4 gigabytes of RAM, a GTX280 video card using Vista 64. Power supply is Cooler Master Real Power Pro 750.

No problems but noticed something. When I play the games, the PSU makes a light hum/whine. I can barely notice it usually, unless I think about it - it is faint.

But on some menu screens, the power supply makes a louder hum/whine. (Edit: I found that if I turn V-sync on, it does not make the hum/whine louder on menu screens. So it seems it was only doing it when the frames per second were really high on menu screens when v-sync was turned off, sine v-sync limits FPS to 60.)

Also, the PSU fan does not ramp up, so the unit is not under stress (plus my system should not be taxing on the 750 watts), and again it is in that game?s menu screen, no 3D play, so the video card should not be under load, when this happens.

What could be causing the hum/whine? It does not seem it would be a load issue. Could it be some kind of feedback caused be some frequency the video card puts out processing something on those screens?

Or does it indicate a problem?

 

[mpilchfamily]

Are you sure its the PSU and not the video card or motherboard. With what your talking about it seams that its likly coming from the video card. All electronics make some sort of noise. There are times where the video card hits just the right frequency of power running threw it that it becomes load ennough to be heard. Chances are there isn't a problem but it is reason enough to get an RMA on the video card. If the new card does the same thing then you'll have to replace the PSU to get rid of it. Not that the PSU is bad its just that the voltage is such that its making the card noisy. A new PSU would be slightly diffrent in the voltage output that the card won't make the noise.

 

[9nines]

I used a cardboard tube (paper twoel middle) to pinpoint the sound and it is coming from the PSU exhaust. If I stick one ear to the tube and hold a finger over my other ear then move the tube around the back of my PC, I can clearly and more loudly hear it in the PSU exhaust. On the video card exhaust I do not hear anything but the sound of air moving.

It sounds like a high frequency vibration. I assume it is a coil vibrating rapidly. Does that seem right? Is that a concern? Could it break from wearing?

Also, it mainly does it in menu screens in Crysis. During actual game play it rarely if ever does it. Turning V-sync on lessens the volume and number of times it does it too. For example, with V-sync off it does it on almost every menu screen and does it louder.

 

[mpilchfamily]

As i mentioned the noise is normal. Chances are it is a coil that isn't glued down as good as it use to be. If you open the PSu up you would see that several parts in there are well glued down to prevent this kind of noise. But there is a chance that its a capacitor going bad.

 

[40sTheme]

Happened w/ my CM eXtreme Power. Turns out the fan control was gimped (IE shut the fan off randomly) and something was heating up and whining whenever it stopped spinning. I'd check on the fan just in case, although you do have a Real Power. I ditched that Extreme Power piece of junk a while back...

 

[9nines]

Coolermaster support suggested that I RMA it to them. I returned it to retailer and got a Corsair TX750W instead.

It does not make the whine/hum.