Here is the time for the NF-S12B to shine. In previous testing it was always asked to push air through a heatsink. This time it was only asked to push air through a box, which is what it was designed to do. It pushed almost as much air as its successor, and made no more noise doing so. Better yet, the results agreed with the fan’s specifications.

Comparing the NF-P14 to its successor, the NF-A15, the P14 produces more airflow, but makes a lot more noise doing so. Six decibels represents approximately double the SPL.

Note that the numbers following the fan names represent the average RPM observed.



PWM

Each fan was subjected to testing with a Zalman PWM Mate, which can be set to approximately 25%, 50%, 75% and 100% PWM duty as well as smoothly varying the fan speed from 25% to 100% PWM duty. The fans were run up and down their speed range, from PWM line grounded (this is the same as 0% PWM duty) to 100% PWM duty. The fan speeds were approximately proportional to PWM duty.

No clicking was heard up and down the entire speed range. No clicking at all. This makes Noctua fans unique.