Any advice on slowing down my noisy Noctua NF12 Industrial CPU fan

[bowrilla]

Well, the IndustrialPPC 2000 PWM versions are reasonably quiet when on low rpm but can produce static pressure like no other fan I know of when needed. I use two NF-A14 2000 PWM on my 280mm radiator and set them to 500-550RPM for anything below 50°C and a very shallow curve up to roughly ~60% at ~75°C on the cpu. Gives a little bit more air in the case and I can remove more heat. Case fans are Silent Wings 3 in their low RPM version set to fixed 650-700rpm-ish (they're literally silent at that speed) and the case is cool and quiet under almost all loads except torture tests. 

Can't recommend AI Suite though - gave me too many terrifying issues (as in: suddenly stopping the pump) and some copy and anti cheat protection detected it as malicious. My BIOS isn't perfect but it works by far better - just some random events pinning the Noctua fans at max rpm for no reason at all. CPU temps drop to 27°C and they still rev like hell. Everything back to normal after a reboot.