Noctua NF-A14x25r G2 PWM chromax.black

State-of-the-art quiet cooling performance for CPU coolers in a sleek all-black design: The chromax.black version of the award-winning NF-A14x25r G2 round-frame 140mm fan.

Succeeding the iconic NF-A15, the NF-A14x25r G2 has quickly established itself as a new benchmark for premium quality quiet round-frame 140x25mm fans.

Its advanced aerodynamic engineering features a novel Progressive Bend impeller design with Centrifugal Turbulator hub, winglets and a record-tight tip clearance of only 0.7mm. These innovations enable the G2 model to provide a significant boost in performance-to-noise efficiency over its renowned predecessor.

At the same time, its etaPERF motor with SupraTorque can leverage extra torque headroom when required, making the NF-A14x25r G2 an ideal upgrade for NH-D15, NH-D15S and NH-U14S heatsinks.

The chromax.black edition combines the NF-A14x25r G2's Sterrox liquid-crystal polymer impeller, comprehensive feature set and breakthrough quiet cooling performance with an attractive black design.

Topped off with Noctua's trusted premium-grade SSO2 bearing, more than 150,000 hours MTTF and a 6-year manufacturer's warranty, the NF-A14x25r G2 PWM chromax.black is the perfect choice for users looking for cutting-edge quality, quietness and performance in an all-black style.

Design

Providing a significant performance boost over the renowned NF-A15, the NF-A14x25r G2 has become a new favourite among quiet cooling enthusiasts. With rave reviews and dozens of awards from hardware media around the world, the G2 model is a proven premium choice for the highest demands.

chromax.black Edition

From the impeller and fan frame to the anti-vibration pads, anti-vibration mounts, screws and cables, the chromax.black edition is black from head to toe, making it easy to integrate into all-black PC builds and various other environments.

Highly Optimised P/Q Curve for All Applications

The NF-A14x25 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-A14x25 G2 is a true jack-of-all-trades with excellent performance in both static pressure 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-A14x25 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-A14x25 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, its 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. This increases overall efficiency by optimising fluid distribution across the impeller area.

Flow Acceleration Channels

The NF-A14x25 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 reduce tip vortices caused by the pressure differential between the suction and pressure sides of fan blades, but they can also reduce efficiency due to extra fluid displacement in high-velocity regions. The NF-A14x25 G2’s small winglets have been carefully fine-tuned to provide consistent efficiency gains while working in tandem with its Progressive-Bend blade geometry, Flow Acceleration Channels and AAO frame.

Ultra-Tight Tip Clearance

The NF-A14x25 G2 has a record-tight tip clearance (the distance between the blade tips and the inside of the frame) of only 0.7mm. This highly ambitious design sets a new benchmark for 140mm fans and helps the NF-A14x25 G2 work more efficiently against back pressure, such as on heatsinks or radiators, by reducing leakage flows through the gap between the impeller and frame.

Sterrox® Liquid-Crystal Polymer Compound

The NF-A14x25 G2’s impeller is made from Noctua’s novel Sterrox® liquid-crystal polymer (LCP) compound, which 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-to-noise efficiency.

Stepped Inlet Design

Noctua's Stepped Inlet Design adds turbulence to the incoming airflow to facilitate the transition from laminar flow to turbulent flow. This 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 passing through the boundary layer created by the Inner Surface Microstructures, flow separation from the suction side of the blades is significantly suppressed. This 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.

SSO2 Bearing

The NF-A14x25 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

To guarantee the highest possible degree of manufacturing precision, minimum tolerance and excellent long-term stability, the NF-A14x25 G2 features 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, which provides super-precise commutation performance. This enables it to convert minimal electrical input into maximum power output with hardly any losses. It also works in tandem with Noctua’s proven Smooth Commutation Drive 2 technology to make the etaPERF™ motor run near-inaudibly.

SupraTorque

Most fans become slightly slower when working against back pressure, such as on heatsinks and radiators, resulting in reduced performance. Enabled by the new NA-FD6 driver IC, Noctua’s SupraTorque™ technology allows the fan to leverage additional torque headroom when required to keep its RPM speed at the desired level, regardless of airflow resistance. This ensures consistent performance even in the most demanding conditions.

PWM Control with Wide Speed Range

The NF-A14x25 G2 PWM can be PWM-controlled from its maximum speed of 1500rpm all the way down to 300rpm. This makes it possible to adjust the fan for maximum performance or near-silent operation using either automatic, temperature-based motherboard speed control or manual controllers such as the NA-FC1.

Stops at 0% PWM

When the fan is set to a 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 turns the fans off and runs completely silently at idle when thermal conditions 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.

Low-Noise Adaptor

The NF-A14x25 G2 is supplied with a Low-Noise Adaptor (L.N.A.) that reduces the maximum fan speed from 1500rpm to 1250rpm. The L.N.A. can be used either to run the fan at a fixed speed of 1250rpm or to cap the maximum speed when using automatic PWM control.

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 splitter cable allows the connection of a second fan to the same PWM fan header for automatic control.

Advanced Protection Features

Protected against reverse polarity, overvoltage and overcurrent (short circuits), the fan is suitable for use in challenging electrical environments. Its ultra-low electromagnetic compatibility (EMC) emissions also make it ideal for applications where electrical interference is critical. Additionally, its locked-rotor and overloading protection provide extra safety in situations where the fan may be mechanically blocked.