Noctua NF-A4x10 FLX, High-Performance Quiet Slim Fan 40mm

A brilliant fan, like all the ones from Noctua, but this one perfectly meets the fan requirements for a Hikvision NVR, in my case the DS-7608NXI. The fan is inaudible whilst still providing good airflow. Now, the only thing you can hear is the power supply fan, which I’m also thinking about replacing at some point. Crucially, the kit includes a 3-pin to 2-pin adaptor, so you don't even need to cut any cables or change the connectors on the plug.

I bought this fan to replace the noisy one included in an old HDD IDE rack I need to use (the cheap supplied fan has become unbearably noisy due to dust after just a few months of everyday use, unfortunately...). This was the first time I bought a Noctua fan, even if I knew this is one of the highest-quality brands of silent fans, and although some people might think this specific kit is overpriced for a small 40x40x10mm fan, I can assure you that the packaging and the accessories included in it are worth the price of the product alone! The fan itself is almost completely inaudible outside of a case, especially when used at reduced speed, which can be obtained by using the clever low-noise adaptor: a small, inconspicuous cable extension, which goes between the fan connecting cable and the power source connector, and lowers the rotating speed from 4500 to 3700 rpm; by the way, the air flow produced even at reduced speed seems considerable anyway, in my opinion. But the most amazing aspect of this product are the supplied accessories included in this gorgeous kit: apart from some typical, high-quality metal screws, you get professional silicon pins, which can be used to mount the fan screwlessly in order to reduce vibrations, an extension cable, an adaptor cable to convert from 3 to 2 power pins, and the most wonderful adapter of them all: the incredible OmniJoin adaptor set, which includes an extension cable ending with 2 truncated red/black power wires, and four _amazing_ "crimp-like" connectors, which allow you to join the truncated power wires to any other corresponding wires coming from _any_ appropriate fan power source inside the PC, _without even having to remove the insulation from the cables_ (!). Basically, in case you want to attach this fan to any "custom" connecting cable with a connector that does not fit any of the included adaptors, you can just cut the connector off of your available custom power cable, and join the resulting truncated black/red wires with the corresponding truncated ones from the Noctua OmniJoin adapter, "crimping" (pressing) the red/black power wires together using 2 of the 4 omnijoint proprietary connectors with flat-nose pliers (not included). If this sounds complicated, actually I assure you it is not, and everything is explained in extremely clear instructions with detailed figures included in the kit, of course. It is a _very_ clever and professional alternative to just "splicing" power cables together with insulating tape, in my opinion! In the future, I will definitely try more Noctua products like this one, in case I need to attach a fan to a custom power cable, hoping they will work with no problems... (Please note that I have _not_ tried the omnijoint connectors, since I do not need them for my specific connector, luckily.) So, all things considered, in my opinion you _definitely_ get what you pay with this amazing product, and I just hope the fan will last for a long time!

I have an 8k system with 5 cameras. My installers fitted an NVR that had no fan, and I had 2 hard drive fails in 9 months. Hik apparently had many such complaints so decided it was down to heat. My installer swapped the box for the same one, but from October 2025 it’s had a fan in it. And that fan was very noisy. After installation my wife walked in the house and thought I had some fan heater on. I could even hear it over the TV it’s plugged into. Cue some research and buying one of these. It was very easy to swap over took 10 mins top, I basically just unplugged the old one, unscrewed two screws to remove and screwed this one in and plugged in. Made sure I put it in so the air is blowing out, not in. It isn’t obvious from the product description, that it comes with a 3 pin to 2 pin adapter. It does. The third pin is for fan control speed Hik of course hasn’t bothered fitting to the NVR so you just need the 2 power pins. Now it’s much better. Far from silent, but I don’t really notice it now and can’t hear it over the TV. In another design fail Hik not only put in a noisy fan, but have it blowing through perforated holes in the case. To make it quieter I could cut out those perforated holes but that would invalidate warranty of the NVR box but I read it makes another quite big difference if I so chose to do so. I’ve retained the original fan to put back in, in case the NVR ever fails or still trashes hard drives. Another method to make it even quieter would be to plug in the included noise reduction wire, but all that does is limit current to the fan and fan speed, so won’t clear as much warm air- not sure about that given the hard drive failures Hik seem to now agree was caused by excessive heat in an uncooled NVR. Please open your box and check the fan size before buying and placement. Different NVRs have different set ups. The one I had was really easy, some Hik NVRs have fans on the in built power supplies and it gets a bit more complicated as you have to take that out to change. Also some May have differing size fans. Many however will be 4cm by 1cm. I couldn’t not have bought one 2cm in depth as it would not have squeezed in the space. So an easy, very quick and simple solution for me, I am delighted.

Don't normally write reviews but hopefully this may help someone. Yes the fans are expensive but the quality is excellent and a 6 year guarantee gives some hope that I won't have to revisit this job for some time. I acquired a 48 port Netgear GS748TP Switch on eBay for a great price. The problem was it sounded like a Jet Fighter and was totally unusable for a home office environment. I saw sets of replacement fans from US sellers on eBay at a crazy price including shipping but wasn't sold on the potential build quality and/or reliability of these Chinese branded overpriced parts. Long story short, after coming up short researching fan requirements for my specific switch, I stripped back the switch and discovered 3x 4020 fans and 2x 4010 fans all running at 12v. Having read a few reports on other switches where people were having trouble getting the Noctua NF-A4x20 FLX fans to work, I decided to take the plunge and order 5x Noctua NF-A4x10 FLX fans. You have to change the pin wiring on these to match the Netgear Red|Blue|Black pin heading so this means changing the Noctua NF-A4x10 FLX fan headings from Black|Red|Yellow to Red|Yellow|Black. This is easy with a small flat headed screwdriver to unlatch them. Once done they spin up beautifully and the noise difference is night and day! Admittedly the airflow throughput isn't anywhere near what the is was with the original fans but this switch is never going to be stretched so for me the compromise to achieve something so quiet (not really audible from 2m away) is well worth it. NB: The only caveat to all this is that fan error warning light on the switch stays lit but this doesn't affect the fans running. If you can live with the additional light then this is a worthwhile mod for a home setup. Will definitely look to use Noctua fans on any future builds/upgrades.

I bought this as a replacement for the stock fan on the Ouya and very pleased with it. It comes in upmarket packaging, with velcro on the front and back that allows you to see the contents. For a fan, there's a lot of extras with it, including some rubberised grommets that are designed to reduce vibration and noise but the best thing is the clever Omni Join system. Although lots of different power connectors are included in the package, the Omni Join connectors (4) allow you to quickly connect any existing connector to the fan by simply cutting the plug off the original fan and attaching the wires to the Omni Join and pushing down to make a connection. Simple and very effective - genius idea! It took about five minutes to install and get working, wasn't sure if it was working at first as it was very quiet. Stripping the Ouya open shown the fan not working so I tested it under load so I could see if it was working. Once it had got warm, the fan indeed did kick in, and while not silent, it was certainly a lot less noise than the original so I'm quite happy with it. Expensive, but worth it for such a high quality, almost silent fan.

I have known about Noctua for a while from PC building community. They really do make good products! The package came with various connectors and well laid out, relatively easy to install! If you are considering replacing your current fans on a 3D printer for these, keep in mind that these will need a buck converter (relatively inexpensive) as these are 12V and your printer could output 24v. This is the case for my Creality Ender 5 pro and basically a lot of the Creality printers. Also use PWM tuning if you have Marlin firmware to ensure the fan and hotend can work together effectively. There are plenty of guides online about explaining the two things. It may have less performance than stock fans but I would rather use the PWM tuning to make it work for my setup and have less noise whilst printing! I can barely hear these running, which sometimes makes me wonder if they are working; my only way is to see it through the hot end shroud when it’s spinning.

Purchased to replace noisy fan in CCTV unit Original - 57.7 db Cleaned original (removed dust) - 56.1 db New (at max 4500 rpm) - 45.8 db New (using lower 3700 rpm harness) - 41.6db (improvement drop of 14.5db) New (3700 rpm) with case modification on CCTV box - 40.1 db The fan noise is vastly improved and now not intrusive for a room. Remembering the db scale is logarithmic it’s very impressive

My CCTV NVR had a very noisy cooling fan, which was very annoying when you spend a large sum of money on the system itself, after some research, I found that a large number of NVR's and DVR's seem to come with these cheap cooling fans made in China which are very noisy in operation. I found that a vast number of people were experiencing the same problem and were fitting this fan to rectify the high noise levels, so I took the plunge and ordered the fan after removing the outer casing of my NVR to measure the fan size first. Make sure you check the voltage which will be printed on the sticker attached to the fan, as you can get 5 volt and 12 volt fans. The fan arrived quickly as it was kept in stock by Amazon, the outer packaging of the Noctua fan was high quality which was a good start. I removed the cheap Chinese fan and fitted the new Noctua unit, I required the (NA-AC2) lead which converts the 3 pin fan connector to a 2 pin connecter, this plugs straight into my Reolink NVR Motherboard socket. The fan unit kit also comes with a further noise reduction lead (NA-RC11), this slows the fan down to a lesser RPM rate which gives you an even quieter fan while still giving me enough cooling capacity for my NVR. The Low-Noise Adaptor lead (NA-RC11) plugs in-line in-between the fan plug and the 3-2 pin converter lead (NA-AC2). All leads come provided with the kit. The result was excellent, I now have a quiet NVR unit.

I installed this Noctua fan in my Reolink RLN16-410 NVR. It did help to lower the noise from the NVR but not a huge amount. I took 10 sound measurements before and after the Noctua fan upgrade. Min and max recorded values were as follows: With original fan: 45.1 - 46.0 dB With Noctua fan: 43.8 - 45.5 dB These NVRs actually run much quieter with the top case removed, so I also took 10 before and after measurements with the case removed: With original fan, case removed: 41.0 - 42.6 dB With Noctua fan, case removed: 38.5 - 40.0 dB These days I'm running the NVR inside a closed cupboard with the Noctua fan installed and the top case removed and I can only just barely hear the running NVR through the closed (internal wooden) door. I think the lingering noise is actually harddrive noise, not fan noise. Hot tip: I previously also applied weather stripping around the door frame which helped a lot to reduce noise leak through the cupboard door.

Fungerar precis som utlovat. Knäpp tyst liten fläkt som flyttar förvånandsvärt mycket luft.

Deze ventilator is de beste in zijn soort super goed

Installed this on an LSI Logic SAS 9207-8i Storage Controller. Perfect fit on top of the heat sync with a couple self taping fasteners. Installing this fan plus repasting the heat sink dropped temps from 180F to 90F. Very quiet even at full speed. This is a 3 pin connector so no PWM, but that's fine as this is very quiet and performs well. This Noctua comes as an entire kit with good cable length plus an extender cable and other accessories. Good value for the money and highly recommended.

Excellent ventilateur, fidèle à la réputation de Noctua. L’installation est simple et tous les accessoires nécessaires sont inclus. Le niveau sonore est extrêmement faible, même à pleine vitesse, tout en offrant un excellent refroidissement. La qualité de fabrication est remarquable et inspire confiance pour une utilisation à long terme. Une solution idéale pour améliorer le refroidissement d’un PC sans augmenter le bruit. Je recommande vivement. Installé sur le nvr reolink