Next-generation performance
Building upon the success of the original NF-A12x25, the G2 version introduces a refined blade geometry and a novel motor design. These advancements lead to a significant boost in performance-to-noise efficiency, allowing the NF-A12x25 G2 to achieve superior results across various applications, including water cooling radiators, heatsinks, and case fan setups.

Highly optimised P/Q curve for all applications
The NF-A12x25 G2’s sophisticated aerodynamic design allows for a pressure to airflow (P/Q) curve that is extremely strong in the critical mid-section. This means that the NF-A12x25 G2 is a true jack-of-all-trades with excellent performance in both static pressure demanding and airflow demanding applications.

Excellent on-application acoustics
While many fans produce unpleasant, high-pitched noises when installed in typical applications such as on heatsinks or radiators, the NF-A12x25 G2 has been carefully fine-tuned for optimal on-application acoustics. It produces a smooth, pleasant frequency profile and surprisingly low sound pressure levels (SPL) when working against back pressure.

Progressive-Bend impeller
The NF-A12x25 G2 features a unique Progressive-Bend impeller with Flow Acceleration Channels and winglets. Its nine blades are swept backwards close to the hub and progressively bent forward further out. Working in tandem with the Centrifugal Turbulator hub, this design not only helps to push more air towards the outer blade areas where efficiency is higher but also assures maximum lift and near uniform loading across the entire blade span.

Centrifugal Turbulator hub
Acting as a turbulator, the new Centrifugal Turbulator hub design improves flow attachment in the hub region. At the same time, it’s centrifugal driving motion pushes air outwards from the hub area where efficiency is low due to the slow rotational speed towards the outer, high-efficiency zones of the blades, thereby increasing overall efficiency by optimising fluid distribution across the impeller area.

Flow Acceleration Channels
The NF-A12x25 G2 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.

Winglets
Winglets can help to reduce tip vortices that are caused by the pressure differential between the suction and the pressure side of fan blades but bear the risk of reducing efficiency due to extra fluid displacement in high velocity regions. The NF-A12x25 G2’s small winglets have been carefully fine-tuned to provide consistent efficiency gains working in tandem with its Progressive Bend blade geometry, Flow Acceleration Channels and AAO frame.

Ultra-tight tip clearance
The NF-A12x25 G2 has an extremely tight tip clearance (distance between the blade tips and the inside of the frame) of only 0.5mm. This highly ambitious design helps the NF-A12x25 G2 to work more efficiently against back pressure, such as on heatsinks or radiators, by reducing leak flows through the gap between impeller and frame.

Sterrox® liquid-crystal polymer compound
The NF-A12x25 G2’s impeller is made from Noctua’s novel Sterrox® liquid-crystal polymer (LCP) compound that features extreme tensile strength, an exceptionally low thermal expansion coefficient and damping characteristics that are ideal for reducing resonance and vibration phenomena in advanced fan-blade designs.

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.

Stepped Inlet Design
Noctua's Stepped Inlet Design adds turbulence to the influx in order to facilitate the transition from laminar flow to turbulent flow, which reduces tonal intake noise, improves flow attachment and increases suction capacity, especially in space-restricted environments.

Inner Surface Microstructures
With the tips of the fan blades ploughing through the boundary layer created by the Inner Surface Microstructures, flow separation from the suction side of the blades is significantly suppressed, which results in reduced blade passing noise and improved airflow and pressure efficiency.

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 screws and most other mounting mechanisms.

Anti-vibration gasket for water cooling radiators
The NF-A12x25 G2 includes an NA-AVG1 silicone gasket that can be used when installing the fan on water cooling radiators or other applications that benefit from a tighter seal with the fan. The gasket helps to damp minute vibrations and to reduce air loss between the fan and the radiator for optimal cooling performance.

Intake side spacer for suction applications (available separately)
If space allows, the NF-A12x25 G2 can be combined with the optional NA-IS1-12 inlet side spacer to reduce influx turbulences in “pull” type applications where the fan draws air through a grill, mesh filter or perforated panel. In many configurations, this reduction in turbulence can enhance airflow performance and further improve the fan’s suction acoustics.

SSO2 bearing
The NF-A12x25 G2 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.

Metal bearing shell
In order to guarantee the highest possible degree of manufacturing precision, minimum tolerance and excellent long-term stability, the NF-A12x25 G2 sports a CNC milled bearing shell made entirely from brass.

etaPERF™ motor with NE-FD6 PWM IC
Noctua’s new etaPERF™ motor sets new standards in energy efficiency thanks to its extremely low electric impedance and the latest NE-FD6 drive system with its integrated, ultra-sensitive Hall effect sensor that provides super-precise commutation performance. This not only enables it to convert a minimal electric input into a maximum power-output with hardly any losses, but also works in tandem with Noctua’s proven Smooth Commutation Drive 2 technology to make the etaPERF™ motor run near-inaudible.

Ultra-quiet low-speed version with PWM
Producing only 11.8 dB(A) at its 1100rpm maximum speed and 7.8 dB(A) with the included Low-Noise Adaptor, the LS-PWM version is ideal for serious silent-enthusiasts: An ultra-quiet low-speed fan that supports PWM control for advanced acoustic fine-tuning!

Stops at 0% PWM
When the fan is set to 0% PWM duty cycle by the motherboard or PWM fan controller, it will stop. This makes it ideal for creating setups with semi-passive cooling that automatically turn the fans off and thus run completely silent at idle if thermals allow.

Smooth Commutation Drive 2
The latest version of Noctua's advanced Smooth Commutation Drive system ensures superb running smoothness by eliminating torque variations and switching noises. This makes the fan remarkably quiet even at very close distances.

Extensive cabling options
The fan's short 20cm primary cable minimises cable clutter in typical applications while the supplied 30cm extension provides extended reach when necessary. Both cables are fully sleeved and a 4-pin y-cable allows the connection of a second fan to the same PWM fan header for automatic control.

Advanced protection features
Protected against reverse polarity, over voltage and over current (short-circuits), the fan is suitable for use in challenging electrical environments. At the same time, its ultra-low EMC emissions make it ideal for applications where electrical interference is critical. Last but not least, its locked rotor and overloading protection add extra safety in situations where the fan may be blocked mechanically.

Safety certifications
Unlike many cheap fans, the NF-A12x25 G2 has been thoroughly tested for electrical safety, immunity and radiated emission. Carrying CE, TÜV, UKCA and UL certifications and meeting all applicable standards (EN 62368-1, EN 55035, EN 55032, UL-507), it is a safe, quality device through and through.

6-year manufacturer’s warranty
Noctua fans are renowned for their impeccable quality and outstanding longevity. Like all Noctua fans, the NF-A12x25 G2 features an MTTF of more than 150,000 hours rating and comes with a full 6-year manufacturer’s warranty.