NF-A9 PWM, Premium Quiet Fan, 4-Pin (92mm, Brown)

Bought this to replace the broken stock fan in my UGREEN NAS DXP2800 and it ended up being a perfect drop‑in upgrade. Noise level: At typical NAS fan curves it’s basically whisper quiet, even sitting on a desk a few feet away. Cooling: Despite the low noise, it moves enough air that my drive and system temps stayed the same or slightly improved compared to the original fan. Cable length: The included cable is long enough to route cleanly inside the NAS without needing an extension or weird bends. Mountability: Standard 92mm mounting holes lined right up; swap took a few minutes with just a screwdriver and no mods needed. Speed and airflow: PWM control works as expected, ramps smoothly under load, and at higher RPMs you get noticeably stronger airflow without a huge jump in noise. Overall, if you’re looking for a reliable, quiet replacement fan for a small NAS or SFF build, this one is worth paying a bit extra for.

This thing is amazing, and it comes with different connectors: Y-connector, an extension, and a quiet connector. This fan is quiet, doesn't rattle on the case due to its rubber padded corners, and it performs well. Very good quality fan.

I bought this Noctua fan to replace the stock fan in my UGREEN NAS, and it’s a huge improvement. The installation was easy, and the difference in noise is night and day—now it runs much quieter. Cooling performance is great too, keeping my drives at a safe temperature. If you want a reliable, silent upgrade for your NAS, this fan is definitely worth it.

Quality stuff. Quiet and strong fans

Since I bought a processor cooler from the very same company, I saw this fan in particular. I wanted to replace my loud stock cooler fan. It was a struggle at first, trying to install the "silicon" screws provided in the packaging, but they didn't work on my computer, which was unfortunate but not a big deal. I ended up having to use the other packaged screws, which actually turned out to be "self-tapping screws". They're not your typical screws, so the point for them is to create its own threads onto the fan's screw holes. The fan does not have its own threads out of the box, so once you screw onto the fan's holes, the "self-tapping screws" cuts into the soft plastic. I thought this was not right, but it turned out to be completely normal based on a quick online search, which made me feel good now. The fan also comes with several extension cables. Overall, after plugging the fan in, it worked like a charm. And it is reasonably much more quieter than my stock computer fan. For a good budget fan that was inexpensive (under $20), I say it was worth it.

works great. I really didn't like the color but this color was cheaper and this was for a lab build so I didn't care. Cable length: good, noise level: Noctua is known for quiet fans, this doesn't disappoint. Mountability: no problems. Airflow: good not great ... but it's only a 92mm fan so it meets expectations

The best fans on the market for noise control, precise operation and long lasting use. These fans move more air then others of the same size. The computer designed blades cut down on fan sound.

I set out to make a "nearly" silent PC, in that I didn't want to go fanless, but I wanted it to have the fans running so slowly (or off) during normal operation that it was silent, and it was only during intensive activities that the fans would ramp up. Through that process I ended up using 5 different fan models from 3 different companies,including this NF-A9. Long story short, I prefer NF-Bx line from Noctua as my favorite and the best value. These NF-Ax series fans are slightly better, but not so much more so to justify the 50% (or so) increase in cost unless you need the vibration free mounting hardware it comes with. (The "B" series doesn't come with that nor with the extra extension and splitter cables the "A" series does.) Some cost saving advice: don't buy a Noctua CPU cooler. Buy a Cooler Master CPU cooler (I went with the Hyper T2 as it is the biggest one that fits in a standard case) and take off the Cooler Master fan and buy one a Noctua fan. For ~$27 combined you get what Noctua wants to charge $60 for. The Cooler Master fan sucks and doesn't allow you to reduce the fan speed below ~30%, so it needs to be replaced if you want to go silent, but the Noctua NF-B9 is exactly the same size fan and it is easy to replace it once you realize you can pull off the rubber pads that obscure the fan screws. Another learning, don't trust that the fan controller on your motherboard is doing everything as it should. First, I had to go into bios and change it to PWM mode as it assumed DC mode for the system fans even though it comes with 4-pin fan headers (DC mode doesn't allow it to spin at nearly as low of a speed). Next, it appeared when I was first testing the B series fan that the lowest it could go in PWM mode is 13% based on the RPM data the motherboard was providing. But then I noticed the fan was still spinning when I put the PWM at 10%, so I figured the fan wasn't providing good RPM data below 13%. (I later noticed that the A series would show RPMs down to 10%, further giving credence to that idea.) Next I noticed it would stop spinning below 10% (both A and B series), so I assumed that was the lowest the fan would go. Not so on either count! I later hooked up the NF-B9 fan to my GPU and it could both spin the fan and read its speed as low as 5% PWM (never tried with the A series fan, but I assume it could go slower too). So apparently my motherboard has it's limits that it won't go below. For all I know, the fan could go even lower than 5%, but that's the best the GPU fan controller will do. (Luckily, even 13% is slow enough to be silent in almost all scenarios.) But the long and short of it, is that with 4 of the Noctua fans (A9 on the CPU, 2x B9 on GPU and 1 B9 on the rear of the case) and leaving the front of the case fan off unless the system gets hot (trying to save a few bucks and not replace the 12" fan unless I need to) as well as an EVGA gold power supply in "eco mode" I have a truly silent PC, where a pretty sensitive dB meter can not detect it being on. I have to do the test in the middle of the night, because even cars going by outside are detectable. But at 3 AM, it reads 21.1 dB with the PC off and 21.1 dB with it on. My stomach gurgles and the stupid thing goes up to 24 dB or I click the mouse and it goes up to over 30 dB so trust me when I say the dB meter is sensitive enough to detect pretty small readings. To be fair and give a caveat, to keep it silent, the fans are running at 13% on the rear of the case, 10% on the CPU and 5% on the GPU. But that's just enough air flow with the good heatsinks that in normal operation the system temp stays around 40 and both the CPU temp and GPU temps stay in the mid 50's. Build details: Intel Core i3-8100 CPU MSI Z370M Mortar motherboard Gigabyte GTX 1050 Ti "Windforce OC" GPU (Note: Gigabyte is the only vendor with a good fan controller on their 1050 GPU. The other companies have junk 2-pin fans.) 2 of 4 GB DDR4 2400 Kingston Fury DIMMs Samsung 960 EVO M.2 SSD EVGA 650 GQ PSU in eco mode