Noctua NF-A4x20-PWM Premium Quiet Case Fan 40x20mm

Warranty 6 Years by Noctua

Maximum speed 5000 RPM
Connector 4-pin PWM header
Dimension 40x40x20mm
Max 14.9 dBa noise levelmax
Airflow: 9.4 m³/h

Featuring advanced aerodynamic design measures such as Flow Acceleration Channels and Noctua’s AAO frame the NF-A4x20 is a highly optimised premium-quality quiet fan in size 40x20mm. The PWM version sports Noctua’s custom-designed NE-FD1 IC for fully automatic speed control via 4-pin fan headers and comes with a Low-Noise Adaptor as well as an OmniJoin™ Adaptor Set for easy connection to proprietary fan headers. Its superb running smoothness reference-class SSO2 bearing and Noctua’s trusted premium quality make it an elite choice for the highest demands.

40x20mm size
Compared to Noctua’s award-winning NF-A4x10 the NF-A4x20 is twice as thick which allows for increased static pressure performance and makes the NF-A4x20 ideal for demanding applications with high flow resistance.

Flow Acceleration Channels
The NF-A4x20 impeller features suction side Flow Acceleration Channels. By speeding up the airflow at the crucial outer blade regions this measure reduces suction side flow separation and thus leads to better efficiency and lower vortex noise.

AAO frame
Noctuas AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as Noctuas proprietary Stepped Inlet Design and Inner Surface Microstructures both of which further refine the fans performance/noise efficiency.

Stepped Inlet Design
Noctuas Stepped Inlet Design adds turbulence to the influx in order to facilitate the transition from laminar flow to turbulent flow which reduces tonal intake noise improves flow attachment and increases suction capacity especially in space-restricted environments.