PC works perfectly fine except CPU Fan never spins

[rdv1001]

The PC boots perfectly, idle CPU temp is ~30°C and the CPU fan itself IS working, as I've plugged it into SYS_FAN 1 just to see if it works, and it does. I've also plugged a case fan into CPU_FAN and it was spinning just fine. Wouldn't that mean that both the CPU fan and its header are fine? Then why is the fan not spinning?
I've pushed the CPU to 52°C using aida64, hoping to reach a threshold of some sort and see if the fan spins. It didn't.
Any help, please? Thanks.

I5 6600k not OC
Gigabyte z170xp-sli
Zalman cnps10x performa+

 

[PC-4LIFE]

You can check if there is any threshold in the BIOS. Review the fan curve, if it's available.

 

[rdv1001]

Well, both the BIOS and the SIV in Gigabyte APP Center show a table with two columns, one being Workload and one being RPM. The case fans have regular values, however the CPU fan has 0 rpm at 20%,30%,40%, all the way to 100%. And I can't change that, because I can't click on Fixed RPM, Smart Fan being the only option

 

[PC-4LIFE]

Well, both the BIOS and the SIV in Gigabyte APP Center show a table with two columns, one being Workload and one being RPM. The case fans have regular values, however the CPU fan has 0 rpm at 20%,30%,40%, all the way to 100%. And I can't change that, because I can't click on Fixed RPM, Smart Fan being the only option

Don't do fixed RPM, switch to smart fan, it's much better as your fan will last longer as it only spins at certain speeds when needed.

 

[rdv1001]

Well smart fan is the way to go, but I can't get the fan to start when it's plugged into cpu_fan in the first place

Is it ok to run the cpu fan on sys_fan 1 and a case fan on cpu_fan?

 

[PC-4LIFE]

Well smart fan is the way to go, but I can't get the fan to start when it's plugged into cpu_fan in the first place

Is it ok to run the cpu fan on sys_fan 1 and a case fan on cpu_fan?

Don't you have another cpu fan header on your motherboard?

You can use the cpu fan with the system fan header, but the fan will change speed according to the system temperature, not the cpu temperature.