I have two mostly identical 35W TDP builds based on the DH77DF desktop board. I am using the system with a large fanless heatsink on the CPU. The case has two fans which I have upgraded in favor for a variety that has PWM control and the capacity to move a larger volume of air. I have connected one fan to the CPU fan header and the other to the system fan header. I, then, adjusted the BIOS setting for both fans to be controlled with the CPU temperature, however the fan on the system fan header never throttles up, only the CPU fan regardless of what I put in the BIOS setting... MS Windows 7 may at fault... Would anyone know a way to have the fans control in an identical manner without combining the PWM inputs of the fans to a single header?
I am sorry you are having problems but let me help you with that.
Please note that the CPU fan header comes with 4 pins meaning that one of those pins is the one in charge of providing the reading information to the system and so the fan will automatically work with it according to the reported temperature.
My recommendation is to check for a BIOS update from the Computer Manufacture.
Here is some information I found. We are not responsible for the information that can be provided in 3rd party websites: