Noctua NF-A4x20 PWM 40 mm Case Fan

The Noctua NF-A4x20 PWM is a 40mm fan engineered for cooling solutions in space-constrained environments. Its 40x20mm frame is suitable for applications such as 1U server racks, network attached storage (NAS) units, and other compact electronics where airflow is required but space is limited. The fan utilizes Noctua's SSO2 bearing, a self-stabilizing oil-pressure bearing designed for operational stability and longevity. It connects via a standard 4-pin PWM header for automatic speed control.

This fan operates up to a maximum speed of 5000 RPM, delivering an airflow of 5.53 CFM and a static pressure of 2.26 mmH2O. The PWM control allows for a wide operational range, enabling the fan to slow down for quieter operation or stop completely for silent idling when supported by the system's fan controller. At maximum speed, its acoustic output is rated at 14.9 dB. The package includes a Low-Noise Adaptor (L.N.A.) to cap the maximum speed, offering a straightforward way to reduce noise levels for specific use cases.

• Features a compact 40x40x20 mm frame for small builds
• Uses a 4-pin PWM connector for automatic speed control
• Delivers a rotational speed of up to 5000 RPM
• Built with a self-stabilizing SSO2 bearing for reliability
• Includes anti-vibration mounts, an extension cable, and a Y-splitter