The goal is silence I want to have 2 x low RPM fans (2x 300RPM) in front and 1 in the back (1x 600RPM). The Noctua Y adapter can still control PWM, so the only problem is I dont know how many watts I can get from one header.
FYI NOCTUA NF-A14 only need 1.5W, so there is high chance it will works, but better to be sure - I dont want to damage MB.
Standard is 12V at up to 1A. Supports up to 12W. You can connect safely.
I am into silence as well.
I have 2 Z390 rigs running in different cases, only difference being amount of installed RAM and vid card
1st system is installed in HaF 922 2x140mm case fans (one front, one top), H80iv2 cooler rear in push/pull (connected to the pump). Corsair PSU is 0 RPM. I don't think its fan has ever turned on. System is quiet. Fans spin down to 450RPM. Love it.
2nd system built in Corsair iCUE220T (non Airlow tempered glass front) - 3x120mm in front, h80iv2 rear (same push pull) Same PSU TX850 0 RPM. I am absolutely amazed at this thing. The fans spin down to 650RPM.
The static pressure and airflow is great. I have never used water cooling before. Was nervous about putting liquid above an $800 card. Its worth it. I will probably never use air cooling on a CPU again.