[SOLVED] one of my Noctua NH-D15 fans is emitting a buzz, even under very minimal/idle load?

[jinko95]

Just finished this build, only problem I've found with it is that one of my Noctua NH-D15 fans is buzzing. I'll include a video, and when I zoom out at the end of the video- it is the left fan on the cooler that creates this buzz.
Wasn't aware of what cpu fan it was at the time, which is why I was holding my phone up against the wrong fan.

Visually, I can't see anything touching, and if I stop the fan with my finger, it stops the buzz. Is this a defective motor issue? Anyone else had this problem?

Help appreciated, build for context minus my drives: https://pcpartpicker.com/list/dFpd2V
Video of buzzing: https://streamable.com/ku87ji

 

[Phaaze88]

Oh, I know EXACTLY what's going on here, from personal experience. It is not a motor issue, but one of aerodynamics.
Don't use the NF-A15 as a pull fan. Push only.
No, the first fan doesn't count because there's extra space between it and the 1st tower.

 

[jinko95]

Oh, I know EXACTLY what's going on here, from personal experience. It is not a motor issue, but one of aerodynamics.
Don't use the NF-A15 as a pull fan. Push only.
No, the first fan doesn't count because there's extra space between it and the 1st tower.

So you recommend putting the fan that's on the left in the video, to clamp over the RAM and being on the right side of the tower? Both pushing the air towards the back?

 

[Nemesia]

Yes. That's what you want. Both pushing air towards the back.

 

[Phaaze88]

Yes.

I tried to do triple fan on my D15S before, that's how I found out about it. Didn't matter if I swapped the fans around, the back one always did it.
Like you, I also noted that there was no physical contact to the heatsink from either the blades nor the center housing. I was using the anti vibration pads too.