Control of the DeepCool Fan Hub Fan Supported by 4PWM Fan Speed 3Pin/4Pin: Users can enjoy improved system performance and significantly increase the cooling capacity within the chassis with FH-04. The FH-04 is compatible with 3-pin and 4-pin fans and can extend up to 4 fans. Design of PWM Functions The fan speed can be simultaneously changed and each port has its own PWM function, but