z270 taichi issue in PWM

lantony wrote: Hi all, this motherboard is great but I have an issue that i am reading around seems to be common: all the 4pin on the motherboard for fan control are working fine except for the CHA FAN 2 which i cannot use at all in PWM mode. It only works in full speed mode, if i try to set the pwm mode, it get simply disabled. I have read of a couple of guys having issues on PWM mode for cha fan 3. What might be this issue? how to solve it? I am running the latest bios (2.10) thanks

The specifications for the Z270 Taichi state:

 "CPU_OPT/W_PUMP, CHA_FAN1, CHA_FAN2 and CHA_FAN3/W_PUMP can auto detect if 3-pin or 4-pin fan is in use.".

So a four pin PWM fan on the CHA_FAN2 connector should have its speed controlled fine.

The CHA_FAN3 connector must be manually configured with its option in the UEFI/BIOS (Chassis Fan 3 Control Mode), to operate in PWM or DC (three pin voltage control) mode.

What is the full model name and number of the fan you are using on the CHA_FAN2 connector?

Most if not all four pin PWM fans can also have their speed controlled in DC/voltage mode. I have used PWM fans on strictly DC three pin fan connectors, and can control their speeds fine.

I don't have your board, and can only go by the manual, which may not be up to date with UEFI updates.

You said you try to set the CHA_FAN2 connector to PWM mode. How are you doing that? The manual does not show a Control Mode option for the CHA_FAN2 connector.

What fan speed profile are you using for the CHA_FAN2 connector? A custom one or a built in fan speed profile? Have you selected non-default fan speed profiles for the other fan connectors?

You also said if you try to set PWM mode, it gets disabled. I don't understand what you mean by that. What gets disabled?