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Smooth Commutation Drive

Next to aerodynamic noise and bearing related noises, the so called "commutation noise" or "switching noise" can play a major role in the noise emission of axial fans with brushless DC motors. At each transition from one stator coil to another, the rotor receives a sudden torque pulse when the next coil switches on. Each of these torque pulses causes a minute deformation of the whole fan structure. Depending on rpm, torque and the material of the fan, this can result in noticeable noises.

Noctua's Smooth Commutation Drive system provides more continuous switching in order to achieve a smoother transition between the stator coils and thereby significantly contributes to the fan's overall quietness. The second generation of this technology (SCD2) further improves running smoothness and reduces minute noises in close proximity to the motor.

05.10.2015 - NH-D15S
Test verdict: "El NH-D15S se convierte, por derecho propio, en el disipador de mejores prestaciones que ha pasado por nuestro laboratorio y sin duda en mi recomendación personal para cualquiera que necesite un disipador silencioso y potente." (Javier Rodríguez,

04.10.2015 - NH-U9S
Test verdict: "Dwa nowe schładzacze firmy Noctua zasłużyły na słowa uznania. Austriacki producent po raz kolejny przygotował urządzenia, które są doskonale wykonane i zapewniają pełną kompatybilność z najnowszymi procesorami oraz płytami głównymi m-ATX." (Marcin Jankowski,

04.10.2015 - NF-F12 industrialPPC-2000 PWM
Test verdict: "Wer also das nötige Kleingeld übrig hat, sollte gleich zum Besten greifen und nach einer passenden Lösung suchen. Wenn man bei der hohen Leistung bleiben will, sind die Noctua NF-F12 industrialPPC-2000 PWM eine perfekte Alternative, da diese um Einiges leiser sind und trotzdem eine brachiale Leistung bieten." (Rene Ruf,

02.10.2015 - NH-U9S
Test verdict: "When building a small from factor rig, the user will have to make those important choices. Luckily the NH-U9S does a pretty great job while staying tiny. We can definitely see it being a solid choice for those looking to build a nice tiny but powerful computer." (Craig O Sullivan,