Question Fan header problem on Intel s1200kp server motherboard

Aug 10, 2020
Hello, i have been trying to control using the BIOS of an s1200kp motherboard a noctua NF-A9x14 PWM fan , the motherboard has only 2 fan connectors, both are 4 pins and are physically compatible with the noctua's connector, the problem is that no matter what duty cycle i select on the BIOS the fan will always be at 100%, the fan header that im using is color red, , ( the link shows the fan header and a 3 pin fan that i'm not familiar with , since the colors of the cables are different than most of the fans that i have used). I am not able to use the white fan header cause my cpu cooler blocks it. I don't know if the person that had the board before me changed the CMOS battery , could a low CMOS battery be causing this? The BIOS saves the date and time ok. The motherboard shows the RPM of the fan. I have tested the fan header using another 120mm fan that also stays at 100% regardless of the duty cycle i specify on BIOS.

Is the noctua fan not compatible with that fan header or the PWM generated by that board?

Do i need to wire differently the noctua fan so the PWM from the motherboard controls it?

How can i test the fan header for faults?

Thank you!