noctua nf-a12x25 pwm, premium quiet fan, 4-pin (120mm, brown) noctua the nf-a12x25 is a highly optimised next-generation 120mm fan that integrates noctua’s latest innovations in aerodynamic engineering in order to achieve an unprecedented level of quiet cooling performance. it takes state-of-the-art technologies such as the aao (advanced acoustic optimisation) frame or flow acceleration channels and combines them with a record tight tip clearance of only 0.5mm, which is made possible by using the novel sterrox liquid-crystal polymer (lcp) compound as well as a metal-reinforced motor hub and axis for ultimate precision. following the approach of noctua’s a-series, the nf-a12x25 is a true all-rounder that yields superb results in all types of usage, regardless of whether it’s in low-impedance, airflow-oriented applications such as case cooling, or high-impedance, pressure-demanding scenarios such as on heatsinks and watercooling radiators. the 4-pin pwm version supports fully automatic speed control via pwm fan headers and comes with a low-noise adaptor to reduce the maximum speed from 2000 to 1700rpm. topped off with exceptional running smoothness, noctua’s reference-class sso2 bearing, a rich bundle of accessories and 6-year manufacturer’s warranty, the nf-a12x25 is a premium-quality product through and through. its superior efficiency, cutting-edge construction and pioneering materials make it an elite choice for the most discerning demands.