For our review, we received one piece of all products, the normal NF-A14x25 G2 PWM, an ultra-quiet version of the NF-A14x25 LS-PWM, and the dual package NF-F14x25 G2 PWM Sx2-PP. Let's start with the normal version. The design of the box is very similar to what we have already seen from Noctua. A lot of technical information is displayed at the back as well as inside the box.

The box feels premium and opening it unveils its contents, as we mentioned earlier, a lot of information for users to understand the tech behind this product. Everything is secured and will arrive without any problem at your home.

The product has normal dimensions of 140x140x25 mm, packs a 4-pin PWM cable with 20cm of length, and inside the accessories box you will also find a 30cm NA-EC1 extension cable in case you need it. The rotation speed is 1500 RPM (1250rpm with L.N.A reducer) and boosts airflow of 155.6 m³/h (127.1 m³/h with L.N.A reducer) and the measured acoustical noise is 24.8 dB(A) (19.7 dB(A) with L.N.A. reducer). The operating voltage is 12 V and Noctua feels very proud that the product can reach an MTTF > 150,000 h. For application-specific optimization, the NF-A14x25 G2 comes with an NA-AVG2-LR anti-vibration gasket pre-installed to create a tighter seal on radiators. Additionally, its AAO (Advanced Acoustic Optimisation) frame can be combined with the optional NA-IS1-14 inlet spacer, which can help to achieve superior suction acoustics and flow rates in challenging intake configurations.

The 4-pin PWM version supports fully automatic speed control via PWM fan headers and comes with a Low-Noise Adaptor to reduce the maximum speed from 1500 to 1250rpm. Its ultra-low-loss etaPERF motor with Smooth Commutation Drive 2 technology doesn’t only provide unprecedented energy efficiency and running smoothness, but thanks to the new SupraTorque feature, it can also leverage extra torque headroom to keep the fan at its desired speed when working against back pressure, thereby ensuring even better performance on heatsinks and radiators.

Inside the retail package you will also find a "warning" about the exact pressure that you must place on each screw to have the best possible results:

Inside the accessories box you will find many goodies:

• NA-RC16 Low-Noise Adaptor (L.N.A.)
• NA-YC1 4-pin PWM splitter cable
• NA-EC1 30cm extension cable
• 4x NA-AV2 anti-vibration mounts
• NA-AVG2-LR anti-vibration gasket
• 4x NA-AVP1-LR load-relief anti-vibration pads
• Fan screws

Passing to the Low-noise version, the NF-A14x25 G2 LS-PWM, we will find a similiar design as with the normal version, even now the fan has been reduced to 800 RPM to reduce noise. Inside the box you will find a NA-RC8 Low-Noise Adaptor (L.N.A.), a NA-YC1 4-pin PWM splitter cable, a NA-EC1 30cm extension cable, 4x NA-AV2 anti-vibration mounts, NA-AVG2-LR anti-vibration gasket, 4x NA-AVP1-LR load-relief anti-vibration pads and four fan screws

The product has normal dimensions of 140x140x25 mm, packs a 4-pin PWM cable with 20cm of length, and inside the accessories box you will also find a 30cm NA-EC1 extension cable in case you need it. The rotation speed is 800 RPM (600rpm with L.N.A reducer) and boosts an airflow of 81.6 m³/h (67.5 m³/h with L.N.A reducer) and the measured acoustical noise is 11.4 dB(A) (8.6 dB(A) with L.N.A. reducer). The operating voltage is 12 V and Noctua feels very proud that the product can reach an MTTF > 150,000 h. Not much to comment on here, very low noise levels for users who might need such an air fan.