Noctua Cooling Solutions
Noctua's premium cooling components are internationally renowned for their superb quietness, exceptional performance and quality.
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 FLX version provides 5000/4400/3700rpm speed settings via the supplied Low-Noise Adaptors and includes the 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.
SSO2 Bearing
The NF-A4x20 features the further optimised second generation of Noctua's renowned, time-tested SSO bearing. With SSO2, the rear magnet is placed closer to the axis to provide even better stabilisation, precision and durability.
Integrated Anti-Vibration Pads
Integrated Anti-Vibration Pads made from extra-soft silicone minimise the transmission of minute vibrations while maintaining full compatibility with all standard mounting systems and fan clips used on heatsinks.
Scope of delivery
- NA-RC10 Low-Noise Adaptor (L.N.A)
- NA-RC12 Ultra-Low-Noise Adaptor (U.L.N.A)
- NA-EC2 30cm extension cable
- OmniJoin adaptor set
- 4x NA-AV3 anti-vibration mounts
- Fan screws
AAO frame
Noctua's AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design and Inner Surface Microstructures, both of which further refine the fan's performance/noise efficiency.
 NF-A4x20 PWM |  NF-A4x20 FLX |  NF-A4x20 5V PWM |  NF-A4x20 5V | |
|---|---|---|---|---|
| Customer Reviews | — | — | — | — |
| Price | — | — | — | — |
| Connector | 4-pin PWM | 3-pin | 4-pin PWM | 3-pin |
| Voltage | 12V | 12V | 5V | 5V |
| RPM | Max: 5000 / Min: 1200 | 5000 | Max: 5000 / Min: 1100 | 5000 |
| RPM with L.N.A. | 4400 | 4400 | - no data | - no data |
| RPM with U.L.N.A. | - no data | 3700 | - no data | - no data |
| Acoustical Noise | 14,9 dB(A) | 14,9 dB(A) | 14,9 dB(A) | 14,9 dB(A) |
| Acoustical Noise with L.N.A. | 12,2 dB(A) | 12,2 dB(A) | - no data | - no data |
| Acoustical Noise with U.L.N.A. | - no data | 8,5 dB(A) | - no data | - no data |
| Size | 40x40x20 mm | 40x40x20 mm | 40x40x20 mm | 40x40x20 mm |
| Colour | Brown & Beige | Brown & Beige | Brown & Beige | Brown & Beige |
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 FLX version provides 5000/4400/3700rpm speed settings via the supplied Low-Noise Adaptors and includes the 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.
SSO2 Bearing
The NF-A4x20 features the further optimised second generation of Noctua's renowned, time-tested SSO bearing. With SSO2, the rear magnet is placed closer to the axis to provide even better stabilisation, precision and durability.
Integrated Anti-Vibration Pads
Integrated Anti-Vibration Pads made from extra-soft silicone minimise the transmission of minute vibrations while maintaining full compatibility with all standard mounting systems and fan clips used on heatsinks.
Scope of delivery
- NA-RC10 Low-Noise Adaptor (L.N.A)
- NA-RC12 Ultra-Low-Noise Adaptor (U.L.N.A)
- NA-EC2 30cm extension cable
- OmniJoin adaptor set
- 4x NA-AV3 anti-vibration mounts
- Fan screws
AAO frame
Noctua's AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design and Inner Surface Microstructures, both of which further refine the fan's performance/noise efficiency.
NF-A4x20 PWM | NF-A4x20 FLX | NF-A4x20 5V PWM | NF-A4x20 5V | |
|---|---|---|---|---|
| Customer Reviews | — | — | — | — |
| Price | — | — | — | — |
| Connector | 4-pin PWM | 3-pin | 4-pin PWM | 3-pin |
| Voltage | 12V | 12V | 5V | 5V |
| RPM | Max: 5000 / Min: 1200 | 5000 | Max: 5000 / Min: 1100 | 5000 |
| RPM with L.N.A. | 4400 | 4400 | - no data | - no data |
| RPM with U.L.N.A. | - no data | 3700 | - no data | - no data |
| Acoustical Noise | 14,9 dB(A) | 14,9 dB(A) | 14,9 dB(A) | 14,9 dB(A) |
| Acoustical Noise with L.N.A. | 12,2 dB(A) | 12,2 dB(A) | - no data | - no data |
| Acoustical Noise with U.L.N.A. | - no data | 8,5 dB(A) | - no data | - no data |
| Size | 40x40x20 mm | 40x40x20 mm | 40x40x20 mm | 40x40x20 mm |
| Colour | Brown & Beige | Brown & Beige | Brown & Beige | Brown & Beige |
Noctua Cooling Solutions
Noctua's premium cooling components are internationally renowned for their superb quietness, exceptional performance and quality.
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