Question Case fan spinning at constant rate (~1400rpm) regardless of BIOS fan curve and settings.

[JojoMagumby]

I recently installed a new AIO cooler in my MSI tower and since it came with fans so I repurposed the old ones which are the same brand (MSI). Everything is solid and responding properly and temps are fine except that one set of 2 fans that are plugged into the system 6 fan header do not seem to be responding to pwm changes. When in the BIOS and editing the fan curve, even if I disable smart fan and send it to zero they continue to spin around 1400rpm. My first guess was something wasn't seated right but everything seems to be plugged in properly. I don't know what the next step in testing would be before it's determined something is bad with the fans themselves.

Specs:

MSI Z590 pro wifi
i7-11700k
rtx 3080
16Gb Ballistix DDR4 ram
MSI Aegeus Case
MSI RGB 120mm fans unknown model

 

[Aeacus]

one set of 2 fans

Are those two fans 4-pin or 3-pin fans?

 

[JojoMagumby]

Are those two fans 4-pin or 3-pin fans?

4pin sadly. That would be an easy fix if they were 3pin and we're not on the right pins .

 

[Aeacus]

You said you're using 6 fan hub. What happens if you re-arrange fan connectors on the hub?

This would tell if the issue is with the fans or with the hub.

 

[Paperdoc]

Any chance those two fans are actually plugged into the PUMP_FAN header, not SYS_FAN6? the PUMP_FAN header normally will run its "fan" at full speed all the time since that is what most AIO pumps are designed to do.