Fan Noctua 40x40x20mm - NF-A4x20-PWM

The fan Noctua NF-A4x20-PWM is a compact 40 x 40 x 20 mm model aimed at situations where space is critical – small cases, SFF systems, network equipment, home servers. The idea here is not maximum airflow, but controlled and reliable cooling in a limited volume. With 4 Pin PWM control and speeds from 1200 to 5000 RPM, you can adjust the balance between noise and cooling according to your needs. The low noise level of 14.9 dBA and the SSO2 Bearing make it a quiet and long-lasting choice.

What you get is a small fan that is not afraid of long, continuous operation. At 5000 RPM, it provides airflow up to 5.53 CFM / 9.4 m3/h, which is more than enough for targeted cooling of high-temperature zones – VRM, drives, network cards, or tight server cases. The consumption of only 0.6 W at 12 V and current 0.05 A means minimal load on the power supply – suitable for systems with multiple small fans. PWM control allows you to keep it almost silent at idle and increase the RPM only under load. With a declared MTBF of 150,000 hours, this is a fan that you install and forget for a long time.

• Compact size 40 x 40 x 20 mm, convenient for tight cases, network and industrial equipment where standard fans do not fit.
• Wide RPM range 1200 – 5000 RPM, allowing for both quiet operation and aggressive cooling when needed.
• Airflow up to 5.53 CFM / 9.4 m3/h, suitable for targeted cooling of hot components in a limited volume.
• Low noise level of only 14.9 dBA, helping to keep the system quiet even under continuous operation.
• SSO2 Bearing for long life and stable operation, especially important under 24/7 load.
• Standard 4 Pin PWM connector for precise RPM control via motherboard or controller.
• Very long life with MTBF 150,000 hours and extended 72 months warranty, which speaks to reliability in the long term.

This fan is suitable if you are doing a compact build, home NAS, router box, or cooling modification in a closed case where a standard 120 mm fan simply cannot fit. It is also suitable for replacing noisy stock fans in network equipment. It is not the logical choice if you are looking for primary airflow for a large case – here the idea is precise cooling of a small space, not massive airflow.

The combination of small size, PWM control, low consumption, and very long life makes Noctua NF-A4x20-PWM a reliable solution for any compact and specialized projects. If you need a “mount and forget” fan for a small system, this model fits that perfectly.