6-POLE FAN MOTOR State-of-the-art technology 6-pole fan motor with three phases for very low power consumption, less vibration and therefore quiet operation of max. 15.5dB(A). IC MOTOR CONTROLLER Advanced PWM function Advanced high-quality IC motor controller reduces electrical noise. Pulse-width modulation (PWM) allows all compatible 4-pin controllers (including those built into many motherboards) to intelligently vary the speed of the fan. model : be quiet! Silent Wings 3 140mm 4-Pin PWM Fan Speed: 1 tag : Case Fans