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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.

26.04.2015 - Donanimhaber Forum NH-L9x65
Test verdict: "Soğutucu seçerken kasa, ekran kartı, ram, anakart gibi bileşenler sizi kısıtlıyorsa NH-L9x65'e bakmanızı tavsiye ederim." (Ali Emre Alıcı, Donanimhaber Forum)

25.04.2015 - NH-L9x65
Test verdict: "Noctua NH-L9x65 to wprawdzie bardzo kompaktowy cooler CPU ale mimo to jest on godnym następcą modelu NH-L9. Po pierwsze oferowana przez niego wydajność już bez problemu wystarczy do zastosowań przy chłodzeniu nawet wydajniejszych procesorów (a przynajmniej jeśli chodzi o jednostki 4-rdzeniowe). Po drugie producent nie rozdziela już tego modelu coolera na wersję dla AMD i wersję dla Intel a zatem jest to rozwiązanie zdecydowanie bardziej uniwersalne." (Łukasz Talkowski,

24.04.2015 - NH-L9x65
Test verdict: "Ci sentiamo di consigliare caldamente il nuovo Noctua per tutti gli usi, non solo per HTPC, tenere testa e battere soluzioni pił grosse dimostra la cura in cui Noctua ripone nei suoi prodotti." (Michele Mura,

22.04.2015 - NH-U9S
Test verdict: "In the end, the Noctua NH-D9L, U9S and L9x65 are certainly among the best 92 mm low-profile coolers in the market that money can buy. For rig builders who are planning to set up a small HTPC and small form factor system, these coolers could be the perfect choice for you!" (Kevin Owi Kheng Him,