Noctua NF-A6x25 FLX fan – 60mm

The NF-A6x25 FLX is a highly optimised, quiet 60 x 25 mm premium-quality fan that incorporates cutting-edge aerodynamic design measures such as Flow Acceleration Channels and Noctua’s AAO (Advanced Acoustic Optimisation) frame system. Smooth Commutation Drive technology and a reference-class SSO bearing ensure exceptional smoothness and outstanding long-term stability. Modular cabling, a Low-Noise Adapter, and a 6-year manufacturer’s warranty make the NF-A6x25 a premium solution for the most demanding requirements.

The impeller of the NF-A6x25 features Flow Acceleration Channels on the suction side. By accelerating airflow in critical outer regions of the fan blades, suction-side vortex shedding is reduced, resulting in greater efficiency and lower turbulence-induced noise emissions. Thanks to an optimised, compact motor design, the hub area of the NF-A6x25 is significantly smaller than conventional 60 mm fans. This allows for a larger blade surface, contributing to the NF-A6x25’s superior pressure and airflow performance.

Noctua’s AAO (Advanced Acoustic Optimisation) frames include integrated vibration pads, a stepped inlet design, and inner surface microstructures, which enhance performance-to-noise efficiency. The stepped inlet design creates more turbulence in the intake, facilitating the transition from laminar to turbulent flow, which adheres better to the frame (flow attachment) and increases suction capacity, especially in confined intake spaces.

The inner surface microstructures within the frame create a boundary layer that interacts with the blade tips. This reduces flow separation on the suction side of the blade tips, significantly lowering tonal noise while improving pressure and airflow efficiency. Anti-vibration pads made of extra-soft silicone minimise vibration transfer and are compatible with all standard screws, common mounting systems, and fan clips used in CPU coolers.

The latest version of Noctua’s SCD drive system eliminates torque variations and switching noises, ensuring exceptional smoothness. This makes the NF-A6x25 surprisingly quiet even up close. The NF-A6x25 features the second-generation version of Noctua’s proven SSO bearing system. In SSO2, the rear magnet is placed closer to the fan axis for improved stabilisation, leading to enhanced precision and durability.

The NF-A6x25 FLX (Flexibility) offers three speed settings—3,000, 2,400, and 1,600 RPM—using the included Low-Noise and Ultra-Low-Noise Adapters, enabling fine-tuning for maximum airflow or minimal noise. The short 20 cm primary cable helps avoid cable clutter in typical applications, while the included 30 cm extension provides additional reach when needed. Both cables are fully sleeved.

Noctua fans are renowned for their flawless quality and exceptional durability. Like all Noctua fans, the NF-A6x25 has an MTBF (Mean Time Between Failures) rating of over 150,000 hours and comes with a full 6-year manufacturer’s warranty.