Noctua NF-A4x20 PWM Fan - 40mm [NF-A4x20 PWM]

The NF-A4x20 PWM is a premium quality, highly optimized, quiet 40 x 20mm fan with PWM control that uses advanced aerodynamic design measures such as Flow Acceleration Channels and Noctua's AAO frame system. Smooth Commutation Drive technology and SSO reference class bearings guarantee superb running smoothness and excellent long-term stability. Modular wiring, optimal control, low-noise adapter and 6-year manufacturer's guarantee make the NF-A4x20 a premium solution for the highest demands.

The features of the Noctua NF-A4x20 PWM at a glance:
- Stylish brown makes for a classy look
- Premium fan with aerodynamic construction
- Extremely low noise emission of max. 14.9 dB(A)
- High static pressure of up to 2.26 mmH2O
- High volume flow of max. 9.4 m³/h
- Connection via 4-pin PWM
- Very high life expectancy of over 150,000 hours
- Long warranty: 6 years

Small premium fan from Noctua
The PWM version differs from the conventional NF-A4x20 in the possibility of changing the speed via pulse width modulation independently of the voltage. The PWM model of the A4x20 is equipped with Noctua's specially designed NE-FD1 IC for fully automatic speed control and comes with a low-noise adapter that allows the maximum speed to be reduced from a maximum of 5,000 to 4,400 rpm. Its performance-oriented maximum speed and the extensive options for speed control as well as the exceptional speed range make the NF-A4x20 PWM a top solution for users who want to achieve a perfect balance between excellent cooling performance and superb running smoothness - no matter whether on heat sinks or for case ventilation!

The impeller of the NF-A4x20 PWM is equipped with so-called Flow Acceleration Channels on the suction side. By accelerating airflow in the critical outer regions of the fan blades, suction-side vortex shedding is reduced, resulting in higher efficiency and lower turbulence-related noise emissions. The pressure and flow rate has been increased thanks to a double depth compared to the NF-A4x10, which makes the fan perfect for applications with higher air resistance.

Noctua's AAO (Advanced Acoustic Optimization) frames have integrated vibration buffers as well as a stepped inlet area (Stepped Inlet Design) and an inner surface microstructure (Inner Surface Microstructures), which enable even better performance/noise efficiency. The graduated inlet area of the stepped inlet design creates more turbulence in the inlet. This facilitates the transition from laminar to turbulent flow, which adheres better to the frame (flow attachment) and thus increases the suction capacity of the fan, especially where the suction area is limited.

The microstructure on the inside of the frame (Inner Surface Microstructures) creates a boundary layer through which the tips of the fan blades move. This reduces the flow separation from the suction side of the blade tips, resulting in a significant reduction in torsional noise and an increase in pressure and airflow efficiency. The anti-vibration pads made of extra-soft silicone reduce the transmission of the smallest vibrations and are also compatible with all standard screws and commercially available mounting systems or fan clips used with CPU coolers.

The latest, further developed version of Noctua's SCD drive system guarantees excellent running smoothness by eliminating torque fluctuations and switching noise. This makes the NF-A4x20 surprisingly quiet, even at close range. The NF-A4x20 is equipped with the further optimized second generation of Noctua's proven SSO bearing system. With SSO2, the rear magnet sits closer to the fan axis for even better stabilization, resulting in further improved precision and durability.

Noctua's fans are known for their impeccable quality and outstanding durability. Like all Noctua fans, the NF-A4x20 PWM has an MTBF specification of over 150,000 hours and comes with a full 6-year manufacturer's guarantee.

Technical specifications:
Format: 40 x 40 x 20 mm
Storage Type: SSO2-Bearing
Leaf Geometry: A Series with Flow Acceleration Channels
Rotational. (+/- 10%): 5,000 rpm
Rotational. With L.N.A. (+/- 10%): 4.400 rpm
Rotational. Minimum (+/- 10%): 1,200 rpm
Flow rate: 9,4 m³ / h
Volume flow with L.N.A .: 8.3 m³ / h
Sound Emission: 14.9 dB (A)
Sound development with L.N.A .: 12.2 dB (A)
Static pressure: 2.26 mm H2O
Static pressure with L.N.A .: 1.75 mm H2O
Max. Power consumption: 0.6 W
Max. Current: 0.05 A
Operating voltage: 12 V
MTBF:> 150,000 h
Connection: 4-pin

Delivery:
Low-Noise Adapter (L.N.A.)
4-pin cable Y
30 cm cable extension
OmniJoin adapter set
NA-AV3 Anti-vibration mountings
4 fan screws

Manufacturer Warranty 6 years