be quiet! Silent Wings Pro 4 120mm PWM - Fan Noise

Finally, be quiet! have a proper fan design that doesn't have any dumb stuff like the SW3 or PW2 does. I think this fan is a good rival to the Noctua NF-A12x25, though I would still expect the Noctua to have the edge in acoustic quality and noise-normalised performance due to the LCP blade material. I think this blade geometry is unique, it doesn't look like an actual copy of anything else (A12x25, Gentle Typhoon etc).