One of these two new fans from Noctua are constructed of Sterrox, which we have seen a fair amount of advertising for recently.  According to the PR, the new material should allow for tighter spacing between the fan blades and the frame of the fan; these feature a minuscule 0.5mm of clearance compared to the common gap of 1.5-3mm.   The Guru of 3D pulled out their anemometer to see if this design has any effect on airflow and in the case of the NF-A12, how the PWM, FLX and ultra low noise adapters change performance and acoustics.  Take a look through the full review to get your answers.

"Especially our fans and your fans, a review on that new Sterrox based Noctua fan. Well, that and many more newly released ones. Noctua recently released new Sterrox manufactured 120mm fans in a wide range of configurations. The NF-A12 series, however, has been a fan series they worked on for four years! In this group test, we'll put nine recent Noctua fans to the test, and compared them in cooling performance, noise levels and airflow."

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CASES & COOLING