Silverstone CPF04 system cable is designed for enthusiasts With need for controlling numerous system fans. It is capable of expanding one motherboard PWN fan header to support up to eight fans. Powered directly by SATA cable from the computer power supply and filtered through a built in 2200f capacitor the CPF04 system cable can provide clean stable voltage to any fan for optimal performance. Equipped with speed detection sensors for accurately controlling eight PWM fans simultaneously It is an excellent solution for system fan expansion. Fan will not start unless SATA power cable is connected. Speed detection and PWM speed control are functional only when motherboard is connected. Speed control function is unavailable for 3 pin fans.