PCI PC Cooler Cooling Fan Speed Controller Control for CPU HDD DDR VGA Power 12V Increase speed to reduce computer part temperature when computer parts are busy. Reduce speed to reduce noise & power consumption when computer parts are free. Supports computer parts with cooling fan, like CPU, HDD, DDR, VGA, etc. Supports input voltage from 5V & 12V and output voltage 12V. Supports revolution from 500-2200rpm.