Mellanox InfiniBand SX6018 - Switch - EMC only - $300 OBO

Got 4xNoctua NF-A4x20 and replaced 4 super noisy stock fans out of HELL.
Default pinout is as follows (you 're looking at terminals, with two smaller hooks facing down, holes facing away):
1.Red +12v
2.Blue Tachometer(RPM)
3.Yellow PWM
4.Black GND

I've unmounted stock fan block, removed wires from white connectors, removed black connectors from Noctua fans, connected wires as above. Below is Noctua color wiring, same layout
1.Yellow +12v
2.Green RPM
3.Blue PWM
4.Black GND

After connecting all of them to board PWM takes effect (without active alarms fans go from ~20% to ~40% in cycles, which makes it unbearable). Even with Noctua low-noise adapter (which kinda makes cycles smoother) it was more irritating that running with 100% speed.
So, I removed PWM wire from each connector. System detects all fans, but can't control them, and it's really quiet!
So, my advice would be to get 3-pin fans and wire them the same way so you would know if one of them really fails.
It's probably not possible to control fans from PPC board, tc daemon just reads data there.

If that helped, please endorse: https://goo.gl/RfjbnG

 

maybe this one pwm fan?
原装SUNON MC40201V2-Q000-S99 4020 12V 0.9W安静4线PWM散热风扇-淘宝网

 

Since this thread had a little more fan-mod talk than the Beware of EMC switches sold as Mellanox SX6XXX on eBay thread I thought I'd ask here. Does anyone know what the slowest fan RPMs the SX6012 will tolerate without alarm?

 

did you found the slowset fan RPMs