The third reason is going to be temperature. With PWM fans, you can set custom fan curves in programs like Fan Control, so that if your CPU or GPU hits a certain temperature, the fan's RPM gets ...
Of course, the standard way of controlling CPU fans these days is with PWM, so he built a circuit which essentially converts the PWM signal from the motherboard into a phantom thermistor.
You can even use the CPU_OPT header to power case fans, but keep in mind that some CPU_OPT have only three pins, meaning they lack PWM functionality. Dealing with the labyrinthine mess of wires ...
be quiet! has announced its latest reverse-flow fans: the Light Wings 140mm PWM Reverse and Light Wings LX 120mm PWM Reverse, ...
The CPU fan measures 120mm and comes with a 4-pin connector.It comes in black colour, and is recommended for those who want a quiet but smooth gaming experience. ARCTIC P12 PWM - 120 mm Case Fan ...