NA-FK1 Redux, Second Fan Upgrade Kit for NH-U12S Redux Cooler

I bought this fan in addition to the NH-U12S cooler, with the single fan the cooler comes with my temps were around 38-45 at idle and around 60-65c under load. With this fan installed in a push-pull configuration, it dropped to around 35-40 at idle and around 50-60 under load. So for $16, it did help to drop my temps a few degrees, which i think is well worth it. It was just as easy to install as the original fan the cooler came with, the only really difference was that the anti vibration pads on this kit were a little thicker than the original fan, but this didn’t make any difference in the install or operation. Noise wise, it is a slight bit louder with this additional fan, but not enough to make a noticeable difference and bother me. It does come with adapters to reduce the noise if you need them, but it’s at the cost of fan speed, so i ended up not using them. Happy with my Noctua products so far, and ill for sure be using them again for any future cooling i may need

Love Noctua, simple as. I got a Noctua NH-U12S Redux for my 5600X a couple of years ago, and stumbled into a 5800x3d. It runs a little hotter, and the UH12S only has one fan, so I got the second one to go with it. Works like a charm... once I figured out how to mount it

Quite efficient and silent. Coupled with another fan of the same, this has been a great purchase. Considering I work and spend most of my time in a room quite hot, while I still play demanding games, I never noticed overheating.

Bought this as part o a bundle with the NH-U12S Redux so I would have a push/pull fan configuration on my cooler. Works great and runs silently, however the anti-vibration pads are about twice as thick than the pads that come with the fan included with the NH-U12S redux. I don't know why this is, but it makes installation a major pain, to the point that this fan sat crooked on my cooler for a few weeks before I decided to tackle it again. If you get this fan, install it FIRST before trying to get the front fan on. It is WAY easier that way.

The NH-U12A Reux is a great cooler. The second Fan is easy to attach and makes a great cooler even better!

These fans do a great job at keeping my CPU cool. They do get a little noisy at higher RPMs, but that's to be expected.

I got this little kit to replace a 140mm fan on a G2 so it would clear my ram. It fit on the G2 and works nicely. No complaints.

The Noctua NA-FK1 Redux Second Fan Upgrade Kit made a noticeable difference in cooling performance, lowering my CPU temperature by about 3°C. While this might not sound like a huge improvement, the real benefit comes from the push-pull configuration, which significantly boosts airflow. With two fans in place, I’ve seen better cooling efficiency, especially under load. The kit also includes 3 fan cables, which are a great bonus for future upgrades or use in other parts of your computer. Overall, I consider this a solid upgrade. While your mileage may vary, adding a second fan to your CPU cooler provides better airflow and cooling. Noctua is well-known for their high-quality, reliable performance, and this upgrade kit continues that legacy. If you’re looking to maximize your CPU cooling, this is a worthwhile investment.