New fans causing annoying resonating sound

[Shoopman]

Bought a 5 pack of Arctic P14 PWM PST fans and installed them today. 3 front intake, one top exhaust, one rear exhaust. They are all controlled via the CPU temperature so they all should be at roughly the same speed. I have a Noctua NH-D15 CPU cooler.

 

Now that it's quiet I can hear a resonating sound, kinda like if someone was using a vacuum in another room, which comes and goes with varying intensity. I can hear it at idle (50% fan speed) as well as under load. Obviously it is super annoying, but I don't know what's causing it.

 

Has anyone experienced an issue like this before? Any steps I can follow to diagnose the problem?

[Chiyawa]

This is normal, but if possible, try adjusting your exhaust speed a little higher. Your case pressure may be to high.

[Ralfi]

7 hours ago, Shoopman said:

I can hear it at idle (50% fan speed) as well as under load.

Is 50% about 750RPM? Play with your fan curves. I have my Arctics run @ 550-650RPM Idle & ~1200-1400RPM Load & they’re good.

 

It doesn’t take much change in fan curve to minimise of even eliminate the resonance. Just try altering it in 10% increments for both idle & load conditions.

[Mikey89]

I think the sound you're hearing is just the vibration coming from inside the case which is generated by the spinning coolers - the sound is indeed kinda like a vacuum now that i think about it.

 

I have 6 fans for cooling in my case and i hear a buzzing sound most of the times but that's just the inside case fans vibrating and yes they do resonate even when idling for me too.

 

Don't worry i don't think anything is wrong with your PC.

[Shoopman]

4 hours ago, Mikey89 said:

I think the sound you're hearing is just the vibration coming from inside the case which is generated by the spinning coolers - the sound is indeed kinda like a vacuum now that i think about it.

 

I have 6 fans for cooling in my case and i hear a buzzing sound most of the times but that's just the inside case fans vibrating and yes they do resonate even when idling for me too.

 

Don't worry i don't think anything is wrong with your PC.

I'm not worried that something is wrong, the sound is just annoying. The slightly better temps are worthless if the PC is emitting substantially more noise.

[jaslion]

22 hours ago, Shoopman said:

I'm not worried that something is wrong, the sound is just annoying. The slightly better temps are worthless if the PC is emitting substantially more noise.

This is kinda stupid but push down on your case with some force and listen if you still hear the noise.

 

Could be you have some resonance going on

[For Science!]

On 8/18/2022 at 3:49 AM, Shoopman said:

Bought a 5 pack of Arctic P14 PWM PST fans and installed them today. 3 front intake, one top exhaust, one rear exhaust. They are all controlled via the CPU temperature so they all should be at roughly the same speed. I have a Noctua NH-D15 CPU cooler.

 

Now that it's quiet I can hear a resonating sound, kinda like if someone was using a vacuum in another room, which comes and goes with varying intensity. I can hear it at idle (50% fan speed) as well as under load. Obviously it is super annoying, but I don't know what's causing it.

 

Has anyone experienced an issue like this before? Any steps I can follow to diagnose the problem?

Do you have any fans in the "pull" configuration on your D15?

[Shoopman]

22 hours ago, For Science! said:

Do you have any fans in the "pull" configuration on your D15?

The fans from the D15 are pointed in the same direction as the rear exhaust fan if that's what you mean.

[For Science!]

21 minutes ago, Shoopman said:

The fans from the D15 are pointed in the same direction as the rear exhaust fan if that's what you mean.

Could you show a photo of it? it would be easiest to see.

[Shoopman]

I made a diagram, probably better than a picture. Black are case fans, grey is the CPU cooling tower, red are CPU fans, and green is the GPU which has 3 fans on it. Blue arrows are the direction of airflow. Last fan on the GPU is a pass-through because it's a 30 series.

[For Science!]

14 hours ago, Shoopman said:

I made a diagram, probably better than a picture. Black are case fans, grey is the CPU cooling tower, red are CPU fans, and green is the GPU which has 3 fans on it. Blue arrows are the direction of airflow. Last fan on the GPU is a pass-through because it's a 30 series.

looks ok to me (my concerns above are not valid). I remember hearing from reviews that Arctic P12 had a particular annoying sound at 50% speed, so this may be related. But it is likely the sound is localized by its placement, so see if you can find out whether it is the front fans, or the rear fans that are mainly resposible for the noise. You may have to set your idle speed faster than 50% if it is resonance. Otherwise, I'm out of ideas. Goodluck.

[Shoopman]

3 hours ago, For Science! said:

looks ok to me (my concerns above are not valid). I remember hearing from reviews that Arctic P12 had a particular annoying sound at 50% speed, so this may be related. But it is likely the sound is localized by its placement, so see if you can find out whether it is the front fans, or the rear fans that are mainly resposible for the noise. You may have to set your idle speed faster than 50% if it is resonance. Otherwise, I'm out of ideas. Goodluck.

That's definitely possible. I need to find the time to get around to it but I plan to disconnect just the front fans and see if I notice a difference, then do the same with just the rear fans to try to narrow it down. Will also try different fan speeds, if 55% for example is a little bit louder but does not produce resonance I'll take that as a win.

 

If none of that works, I might have to plug each individual fan into its own header to guarantee that they are not synchronized as I've seen some other posts saying that some fans will resonate naturally if too many of them are close enough in speed.

[Shoopman]

Just an update for anyone finding this thread in the future:

 

I will be returning these fans. The humming they emit is extremely annoying and nothing I do makes it go away short of setting the RPM so low that the fans are no better than the ones I replaced (<40%). Of course, the noise also goes away at very high RPMs, but at that point the overall noise level is so high that it doesn't matter. I found that the fans emit a constant or near constant noise between 40% and 60%, the ranges that I would be most commonly using.

 

I did verify that the noise is not caused by several fans set to the same RPM. I attached each fan to its own fan header and tested them individually. Every one of them makes noise in the previously stated RPM range. Setting them all to the same RPM amplifies the noise, but setting them to different RPMs within the noisy range just changes the pitch so that you have five different, slightly quieter hums instead of one loud hum.

 

I was able to find a video of the problem I am experiencing:

 

It sucks but it looks like I will have to spend substantially more on something else that will not hum like this because IMO this noise is unacceptable if you value your own sanity.