Noctua NF-A4x20 PWM, Premium Quiet Fan, 4-Pin (40x20mm, Brown)

I got these as an upgrade for my 3D printer, and it’s been a total game-changer. The stock fans were loud and annoying, but this Noctua runs super quietly while still pushing a good amount of air. My printer’s hotend stays cool without the constant buzzing noise.The build quality is top-notch, as expected from Noctua, and required no soldering due to the omni-join connectors, even with the 3-pin connection. I also love the anti-vibration mounts that help keep things extra quiet.If you're looking to reduce noise on your 3D printer without sacrificing performance, this fan is worth every penny. My prints are smoother, my temps are stable, and I can actually hear myself think now!

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!

The Noctua NF-A4x10 FLX is nothing short of a fanatical fan's dream come true. This little marvel has left me awestruck, and it absolutely deserves a solid 5-star rating. Let me break down why this fan has me singing its praises, and don't even get me started on the vast array of included accessories.Silent Powerhouse (5/5): First things first, the noise level - or should I say, the lack thereof. This fan is so quiet; it's like a whisper in a library. You can barely tell it's running, even at full tilt. It's a game-changer for anyone who values a peaceful computing environment.Impressive Cooling (5/5): Despite its tranquil operation, this fan knows how to keep things cool. It might be small, but it packs a punch when it comes to airflow. Whether you're cooling your CPU or improving case ventilation, it gets the job done efficiently.Flexible Speed Control (5/5): The FLX in its name stands for "flexible," and it lives up to the title. With the included Low-Noise Adapters and Ultra-Low-Noise Adapters, you can fine-tune the fan's speed and noise levels to your exact liking. It's all about customising your cooling experience.Noctua Quality (5/5): When you invest in a Noctua product, you're investing in quality. This fan is no exception. The build quality is top-notch, and it comes with a 6-year warranty, which speaks volumes about the manufacturer's confidence in their product.Easy Installation (5/5): Installing this fan is a breeze. Noctua includes all the necessary mounting hardware and even provides clear, concise instructions. Even if you're not a tech wizard, you'll have no trouble getting this fan up and running.Now, let's talk about the incredible array of included accessories. Noctua doesn't just give you a fan; they provide a complete package. You'll find a variety of adapters, extensions, and even a low-noise adapter, allowing you to tailor your setup precisely to your needs. It's like a treasure trove of options for achieving the perfect cooling solution.I must add that I used this fan to replace the noisy Hikvision NVR standard fan. The difference was night and day. No more intrusive fan noise disrupting my work or leisure. In a nutshell, the Noctua NF-A4x10 FLX is a silent powerhouse that's perfect for anyone who demands both performance and tranquillity from their cooling solutions. Its ability to keep things cool without uttering a peep is nothing short of remarkable. Whether you're building a new PC or looking to upgrade your existing system, this fan is a game-changer. I couldn't be happier with my purchase, and I highly recommend it to fellow PC enthusiasts. It's a 5-star gem! ⭐⭐⭐⭐⭐