The Noctua NH-U12S Redux Cooler Review: Bringing Noctua's Best To a Lower Price

Testing Results, Maximum Fan Speed (12 Volts)

Starting things off, let's take a look at the NH-U12S Redux performance with the fans at their full speed (12 V).

Noctua claims that the NH-U12S Redux can perform just as well as the more advanced (and expensive) NH-U12S, just at the expense of higher noise. Our thermal testing reveals that this claim is true, as the NH-U12S Redux does perform almost identically compared to the NH-U12S. The thermal performance of the NH-U12S Redux is just a little worse than the NH-U12S without the addition of the extra NA-FK1 fan. Adding the NA-FK1 fan makes the NH-U12S Redux a little bit better than the NH-U12S but the actual performance difference is very small.

When it comes to acoustics, Noctua’s statement regarding the amount of noise generated by the NH-U12S Redux is also true. The NH-U12S Redux is noticeably louder than the NH-U12S – though not by much. With its fan running at maximum speed, the noise output of the cooler is not too high at all. Meanwhile, adding the second fan increases the noise output of the NH-U12S Redux a bit more.

Testing Results, Low Fan Speed (7 Volts)

Switching things up a bit, let's next take a look at cooler performance with the NH-U12S Redux fans taken down to 7 Volts.

With the speed of its fans reduced down to about 620 RPM, the NH-U12S Redux still performs almost just as well as the NH-U12S. The addition of the NA-FK1 fan here does make a difference, improving the thermal performance of the NH-U12S Redux significantly and pushing it close to the significantly larger NH-U12A.

Both the NH-U12S Redux and the vanilla NH-U12S are practically dead silent under these operating conditions. The NH-U12S Redux has a noise output 1.6 dB(A) higher than that of the NH-U12S, which is technically a significant difference due to the logarithmic scale, yet on an absolute basis, 32.1 dB(A) is very low and you'd really need to focus to notice that kind of noise in a quiet room. The addition of the second fan makes the NH-U12S Redux more noticeable, but 33.8 dB(A) are very comfortable for everyday use.

Thermal Resistance VS Sound Pressure Level

During our thermal resistance vs. sound pressure level test, we maintain a steady 100W thermal load and assess the overall performance of the coolers by taking multiple temperature and sound pressure level readings within the operating range of the stock cooling fans. The result is a graph that depicts the absolute thermal resistance of the cooler in comparison to the noise generated. For both the sound pressure level and absolute thermal resistance readings, lower figures are better.

In the above chart, we can discern that the NH-U12S is indeed better than the NH-U12S Redux when both the thermal performance and acoustics are taken into account. The NH-U12S Redux does offer great overall performance though, rivaling even that of the NH-U12A under certain conditions where the fan of the latter becomes too noisy for the thermal performance the cooler offers. We can also see that the addition of the second fan makes the NH-U12S Redux capable of reaching slightly lower thermal resistance figures, though always at the disproportionate expense of noise.