Showing results for 
Search instead for 
Did you mean: 

Can't adjust FAN speed

Level 7

Hi there !
I have an Asus ROG STRIX B550-A GAMING motherboard with AMD Ryzen™ 7 5800X3D and for processor cooling, Corsair h100i RGB Platinum SE white with another 4 Corsair LL120 White RGB on the case. I just installed it and my case fans runs to fast , it increase their speed at the same time as using the processor. The fans act as CPU fans although they are mounted directly on the motherboard on CHA FAN 1 and 2 headers . The other 2 fans from the processor heatsink that are connected to the pump and the pump connected to USB header on the motherboard , run just fine at low speed.

To mention that I updated the bios and it still shows over 4000 rpm in the bios fan profile.


Super Moderator

Hi RanysR,

Go into the UEFI and tab over to Monitor, then enter Q-FAN Configuration > Chassis Fan. You can change to your preferred source there if you have one (T-Sensor probe, etc)

Alternatively, Go to QFAN on the landing page and set a fixed fan speed.

13900KS / 8000 CAS36 / ROG APEX Z790 / ROG TUF RTX 4090


 The problem is that tha case FAN RPM increases as the CPU fan RPM increases. Changed the cooler with a deepcool air cooler, AG400 RGB and the problem still remaines. The case fans are conected to a carsair controller, iCUE Commander Core XT that is conected to the motherbord using the USB 2.0 port.

I can't figure this problem out.

Ran Cinebench 2024 for stability test and al the fans started to increase the RPM and the case fans started soundign like they are prepared to take off.

Please help!

Thank you 

Hi, have you adjusted the step up and down levels? You can do this from Chassis Fan Configuration under Monitor

Level 0 - Instantaneous change in speed

The higher the level, the slower the change in fan speed, which may result in less noise but worse heat dissipation.


13900KS / 8000 CAS36 / ROG APEX Z790 / ROG TUF RTX 4090