NF-A4x20 FLX, High-Performance Quiet Fan 40mm | High Airflow, Low Noise, 20mm Thick, for PC and Electronics Cooling, 3 Speed Settings 5000/4400/3700rpm 3-Pin

Replacing like for like in a Netgear switch, these didn't work at all.

Item came up damaged, seller offered UPS return that is completely unavailable where I am from, closest one is 45min drive, it would cost me more that it is worth refund, I got stock with damaged item

Not silent forgot to send it back

Fantastic!! I put this in my Marshall JMT615 Valve Amp, as there is is known over heating issue with these due to heat rising from the power valves and into to the chassis head containing the capacitors, resistors, wiring, pcb, etc. I placed an aluminium plate between the power valves and the head housing the capacitors, etc. This fan then draws heat from the head housing down onto the aluminium plate (not the valves), keeping the enclosure relatively cool, but allowing the valves to get as hot as they need to. Anyway - it's super quiet - If I place my ear close to the amp I can only just hear it with the amp off. If you weren't listening for it, you wouldn't notice it at all. With the amp on I can't hear it at all. I used this to replace a normal 40x10mm fan that put out the usual fan noise and you easily hear that one, and was unbearable. The accessories supplied with the fan were really useful for replacing this. Basically converting this 3 pin fan to my 2 pin supply. Now no noise. Well worth the money. Happy Days!!

Good value for money, with good speed and airflow. Maybe slightly more load than I was expecting but that might be because of the airflow in my storage bay. It is certainly much quieter that the factory fan that the storage bay came with. This also came with adaptors that enabled me to use the original 2 pin connector, I just cut the wire from the original fan, attached the adaptors and it worked just fine. It only took me 10 mins to complete the installation so very easy. Happy with the item!

The technician said this fan doesn’t come with a 2 pin plug so not fit for purpose, used the older version fan 4flx 10mm Which comes with a 2 pin connector. Noise is reduced more than half but still can hear little bit.

The thing about Noctua fans is that the cfm is so low. Yes they are super quiet but check that your application will be ok with the reduction in cooling.

The Noctua NF-A4x20 FLX is a premium quiet fan known for its exceptional build quality and performance. Designed with advanced aerodynamic engineering, this 40x20mm fan provides efficient cooling while maintaining low noise levels. Its 3-pin connector ensures broad compatibility, making it ideal for a variety of applications, from computer cooling to DIY projects. Users appreciate its robust design, long lifespan, and the inclusion of multiple mounting options. Overall, the NF-A4x20 FLX is a top choice for anyone seeking a reliable and silent cooling solution.

I bought a new TP-Link Switch and it was ridiculously noisy. I mean, I get that its supposed to live in a server room but surely they could've done something to tone it down a bit. Two of these to replace the ones inside the switch have made it almost silent while still providing sufficient airflow.

I have replaced stock fans from my Unifi Ubiquiti USG Pro and I here the sound barely, before with stock fans I mom used to complain about noise while she was in other bedroom. Now no sound from the fans at all, for your reference I am not using any low noice adaptors. I will purchase two more to replace in 24 port PoE switch.

Works great in my switch, way quiter and moves the same amount of air.

安定のノクチュアです ウンチ色じゃなければ全てのファンをノクチュアに交換したいくらいです

Very nicely packaged and has all the connections needed for different situations