New Case/PSU "humming" loudly from time to time

[Sonikku]

I got a new case and power supply for my system and often times it's extremely quiet. But sometimes after running for a few days it has an inconsistent humming sound. It isn't super loud, but is loud and inconsistent enough to slowly drive me crazy. I've tried unplugging the case fans and I even unplugged my Evo 212 cpu cooler for about a minute on start up and the noise was still there. I concluded the only thing with a fan still spinning could only have been the power supply. Being the R4, it has grates on the bottom so I screwed the power supply in upside down.

The new case is the Fractal R4. All the sound dampening padding is still in and the only two fans other than the psu and the evo 212 are the front and rear fans the case came with. They are inaudible. The power supply is the EVGA 100-B1-0600-KR.

System specs:
intel i5 2500
8gb gskill ram
Radeon 7770
Crucial 250gb ssd

I notice that when I press firmly on the front of the case it seems to remedy the sound somewhat. Is it the psu acting up or could the rivets in the case be off?

 

[bononos]

Its the vibrations from the faulty fan being passed on to the case. I've had the same issue with case and gpu fans. Try using a spare psu if you have one to know for sure.

 

[TheELF]

Could also be a mechanical hard drive synchronizing with your case.

 

[JeffMD]

not sure what you expecting. Obviously something moving like a fan or HD is rattling, and I am definitely not going to find it any easier than you are. -_-

 

[DigDog]

i'm going to guess "resonance".

does it disappear immediately when you shut off the system, and not come back for a while if you reboot right away ?

it's resonance.

probably just fix it with a set of washers for the PSU screws; or else, even just move the case a bit (generally the floor it sits on contributes) or place *anything* under the case's feet.

if it's not resonance, idk. i find it hard to believe that it's anything else, and having worked with the R4 (which is super sturdy, but it can contribute as it's rigid) this is my best guess.

 

[nerp]

Can you make the sound go away or change by holding on to any of the case panels or drive cages or anything like that?

 

[UsandThem]

Might be a long shot, but I have a R5 case.

I have built it using parts with quietness the biggest priority.

I was getting a weird humming sound that only lasted a few minutes here and there.

What I discovered was causing my issue was my two Noctua fans. I have both a NF-AF14 flx and a NF-A14 pwm.

What it turned out to be, was both of those fans hummed when they ran around 825-840 RPM. RPMs above and below that do not make that humming noise.

Maybe your PSU fan might be doing the same thing.

 

[myocardia]

Can you make the sound go away or change by holding on to any of the case panels or drive cages or anything like that?

I notice that when I press firmly on the front of the case it seems to remedy the sound somewhat.

Maybe your PSU fan might be doing the same thing.

I'm gonna go out on a limb here, and guess that the OP has hooked his two case fans to his motherboard, instead of letting them run wide open, and he's getting resonance from time to time, because of it. OP, immediately change the settings in your BIOS to run your case funs @ 100% at all times, instead of letting the BIOS raise and lower their speeds, to see if that makes the hum go away. It sounds to me as if that's your problem.