The Noctua NF-A12X25 G2-PWM-SX2-PP Fans deliver superior performance and outstanding quietness of operation while providing superb smoothness and excellent long-term stability. Featuring a set of two fans offset in speed, optimising push-pull operation. With an overhauled blade and motor design, a major boost in noise efficiency, highly optimised P/Q curve for all applications, flow acceleration channels for better efficiency, AAO frame for improved acoustics, and integrated anti-vibration pads, these Noctua fans are a highly optimised cooling solution.

 

Features

Noctua NF-A12X25-G2-PWM-SX2-PP Fan

The NF-A12x25 G2 PWM Sx2-PP is a set of two NF-A12x25 G2 PWM 120mm fans that are offset in speed, which can be beneficial in push-pull operation as well as in situations where two or more fans are operating side by side, such as in case cooling applications or on 240 and 360mm water cooling radiators. When two fans are running at almost the same, constant speed in a push-pull configuration or, albeit to a lesser extent, side by side, their acoustic interaction can lead to undesirable harmonic phenomena such as intermittent vibrations or periodic humming due to interference, which can be heard as beat frequencies. Therefore, the two NF-A12x25 G2 PWM fans contained in the Sx2-PP set are slightly offset in speed (+/- ~50rpm) in order to avoid such phenomena. This fine-tuning is made possible by the fans’ novel etaPERF™ motor and its NE-FD6 driver IC that achieves extremely precise speed control and, thanks to its SupraTorque™ feature, can leverage extra torque headroom to keep the exact desired speed even when working against significant flow resistance such as on water cooling radiators and heatsinks. With one fan running ~50rpm slower (PPA) and one ~50rpm faster (PPB), the overall cooling performance can be kept the same while efficiently preventing intermittent vibrations or periodic humming. Since the perception of beat frequencies can vary depending on psychoacoustic preferences, users can easily further optimise acoustics by slowing the PPA fan down a little more through PWM control or the supplied Low-Noise-Adaptor, which will result in an even smoother sound signature due to the increased offset. If more than two fans are running side by side, customers can either combine multiple Sx2-PP sets or add a single NF-A12x25 G2 PWM fan and reduce its speed to the level of the PPA model (~1750rpm) using PWM control in order to make sure that neighbouring fans are never running at the same speed.

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.

Dual Fan Set for Push-Pull and Side-by-Side Usage

Bundling two NF-A12x25 G2 PWM fans that are speed-offset by +/- ~50rpm in order to avoid undesired acoustic interaction phenomena, the Sx2-PP set is the ideal choice for push-pull configurations as well as situations where two or more fans are operating side by side such as on 240 and 360mm radiators or in typical case cooling applications.

Speed-Offsetting Three or More Fans

If more than two fans are running side by side, Sx2-PP sets can be combined to avoid situations where two neighbouring fans run at the same speed level. If the total number of fans is uneven such as when equipping a 360mm radiator, customers can add a single regular NF-A12x25 G2 PWM fan to the Sx2-PP set(s) and reduce its running speed to the level of the PPA fan (~1750rpm) through PWM control.

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.