Noctua NF-A4x20 FLX Computer case Fan 4 cm Beige Brown The Noctua NF-A4x20 FLX computer case fan is designed to provide excellent performance and quiet operation. This 4 cm fan is an ideal solution for smaller computer cases where space is limited. The fan has a unique design that enables better ventilation and cooling. This ensures that your computer remains cool and efficient even in demanding conditions. The fan's beige and brown color scheme fits well with different case styles and brings an elegant look to your computer. The Noctua NF-A4x20 FLX fan also has flexible installation options. You can install it either horizontally or vertically, which makes it suitable for different uses. In addition, the fan has the FLX feature, which enables the selection of three different speed settings. You can adjust the fan speed according to your needs and create optimal cooling. The Noctua NF-A4x20 FLX computer case fan is a reliable and durable choice that guarantees long-term performance. Get yourself this high-quality fan and improve the cooling and performance of your computer.
Noctua NF-A4x20 FLX Computer case Fan 4 cm Beige Brown The Noctua NF-A4x20 FLX computer case fan is designed to provide excellent performance and quiet operation. This 4 cm fan is an ideal solution for smaller computer cases where space is limited. The fan has a unique design that enables better ventilation and cooling. This ensures that your computer remains cool and efficient even in demanding conditions. The fan's beige and brown color scheme fits well with different case styles and brings an elegant look to your computer. The Noctua NF-A4x20 FLX fan also has flexible installation options. You can install it either horizontally or vertically, which makes it suitable for different uses. In addition, the fan has the FLX feature, which enables the selection of three different speed settings. You can adjust the fan speed according to your needs and create optimal cooling. The Noctua NF-A4x20 FLX computer case fan is a reliable and durable choice that guarantees long-term performance. Get yourself this high-quality fan and improve the cooling and performance of your computer.
in 27 offers
last seen 4 Oct 2026
The lowest price we last saw for Noctua 40mm NF-A4x20 Flx 5000RPM Fan was $22.20 at Quiet PC, compared across 23 retailers (last seen 4 Oct 2026). Prices may have changed since.
The all-time low we recorded was $15.52 on 17 July 2025.
Prices last updated 4 Oct 2026.
Noctua 40mm NF-A4x20 Flx 5000RPM Fan
Noctua NF-A4x20 FLX Computer case Fan 4 cm Beige Brown The Noctua NF-A4x20 FLX computer case fan is designed to provide excellent performance and quiet operation. This 4 cm fan is an ideal solution for smaller computer cases where space is limited. The fan has a unique design that enables better ventilation and cooling. This ensures that your computer remains cool and efficient even in demanding conditions. The fan's beige and brown color scheme fits well with different case styles and brings an elegant look to your computer. The Noctua NF-A4x20 FLX fan also has flexible installation options. You can install it either horizontally or vertically, which makes it suitable for different uses. In addition, the fan has the FLX feature, which enables the selection of three different speed settings. You can adjust the fan speed according to your needs and create optimal cooling. The Noctua NF-A4x20 FLX computer case fan is a reliable and durable choice that guarantees long-term performance. Get yourself this high-quality fan and improve the cooling and performance of your computer.
Noctua NF-A4x20 FLX Computer case Fan 4 cm Beige Brown The Noctua NF-A4x20 FLX computer case fan is designed to provide excellent performance and quiet operation. This 4 cm fan is an ideal solution for smaller computer cases where space is limited. The fan has a unique design that enables better ventilation and cooling. This ensures that your computer remains cool and efficient even in demanding conditions. The fan's beige and brown color scheme fits well with different case styles and brings an elegant look to your computer. The Noctua NF-A4x20 FLX fan also has flexible installation options. You can install it either horizontally or vertically, which makes it suitable for different uses. In addition, the fan has the FLX feature, which enables the selection of three different speed settings. You can adjust the fan speed according to your needs and create optimal cooling. The Noctua NF-A4x20 FLX computer case fan is a reliable and durable choice that guarantees long-term performance. Get yourself this high-quality fan and improve the cooling and performance of your computer.
Last updated at 04/10/2026 22:24:18
Cooling Fan for Noctua NF-A4x20 FLX DC12V 0.6W 0.05A 40 * 40 * 20mm 3Pin
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Noctua NF-A4x20 FLX 12V 5000RPM 40x20mm Quiet Cooling Fan
Delivery $11.76
Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown)
Delivery $9
40mm Noctua NF-A4x20-FLX
Free delivery between Wed – Thu
Noctua FLX 40mm Fan (NF-A4X20-FLX)
Noctua NF-A4x20 40mm FLX 5000RPM Fan Brown SSO2 Bearing 3-Pin Connector Low Noise Adapter
Free delivery between 7–12 Oct
Noctua FLX 40mm Fan NF A4X20 FLX - 40mm Case Fans
Delivery $12.40
Noctua FLX 40mm Fan NF A4X20 FLX - 40mm Case Fans
Delivery $12
Noctua NF-A4x20 40mm FLX 5000RPM Fan
Delivery between Wed – Fri $15
Noctua NF-A4x20-FLX 40mm NF-A4x20 FLX 5000RPM Fan
Delivery between 8–13 Oct $14.50
originally posted on mwave.com.au
Noctua have a well deserved reputation for making quiet fans great for computer upgrades, or in my case - Unifi Switch upgrade. The original fans might be great in a dedicated comms centre but much too loud for domestic use. The NF-A4x20 make a huge difference.East install with the comprehensive cable kit provided.Very happy
originally posted on ebay.com
I bought this for the back of my laptop safe, which houses my 16 camera CCTV box and the two 10A plus one 2A transformers. It was there to take away any heat but when I got the fan I added 35 x 40mm holes into the sides to avoid overheating to be on the safe side. This 40mm 12v fan makes no sound whatsoever, even when placed next to your ear. But its lacking in power due to its tiny size and it only removes about 1.5 square feet per minute so dont expect to use it for any serious heat clearance. If I could order again, Id buy the 80mm version and a 80mm hole saw drill for fitting to get the extra power. Ive given this 5 stars because it works well depending what you want to use it for. Its my fault that I didnt order the more powerful version.
originally posted on pccasegear.com
Recently purchased two 40mm Noctua fans to replace the two existing 12 volt fans in an 8 channel NVR that was was unacceptably noisy in a home. The Noctua fans came ready to install with a 4 pin plug on the PWM type and 3pin plug on the FLW type. The fans also came with wire connectors and silicone anti vibration Connectors both with a 6 year warranty. The result was an immediate reduction of around 20dbA in noise withe the 2 new fans however the Noctua fans move around 30% less air the case temperature of the NVR in one location was around 2 degrees C warmer. The only other consideration would be that this successful modification may compromise the NVR warranty if there was an issue during the NVR warranty.
| General | |
| Product Type | Case fan |
| Package Content | Screws, OmniJoin Adaptor Set, extension cable (30 cm), NA-AV3 anti-vibration mounts |
| Width | 4 cm |
| Depth | 4 cm |
Cooling Fan for Noctua NF-A4x20 FLX DC12V 0.6W 0.05A 40 * 40 * 20mm 3Pin
Affiliate Disclosure: We may receive a small commission for purchases made through this link at no extra cost to you. This helps support our site. Thank you!
Noctua NF-A4x20 FLX 12V 5000RPM 40x20mm Quiet Cooling Fan
Delivery $11.76
Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown)
Delivery $9
40mm Noctua NF-A4x20-FLX
Free delivery between Wed – Thu
Noctua FLX 40mm Fan (NF-A4X20-FLX)
Noctua have a well deserved reputation for making quiet fans great for computer upgrades, or in my case - Unifi Switch upgrade. The original fans might be great in a dedicated comms centre but much too loud for domestic use. The NF-A4x20 make a huge difference.East install with the comprehensive cable kit provided.Very happy
I bought this for the back of my laptop safe, which houses my 16 camera CCTV box and the two 10A plus one 2A transformers. It was there to take away any heat but when I got the fan I added 35 x 40mm holes into the sides to avoid overheating to be on the safe side. This 40mm 12v fan makes no sound whatsoever, even when placed next to your ear. But its lacking in power due to its tiny size and it only removes about 1.5 square feet per minute so dont expect to use it for any serious heat clearance. If I could order again, Id buy the 80mm version and a 80mm hole saw drill for fitting to get the extra power. Ive given this 5 stars because it works well depending what you want to use it for. Its my fault that I didnt order the more powerful version.
Recently purchased two 40mm Noctua fans to replace the two existing 12 volt fans in an 8 channel NVR that was was unacceptably noisy in a home. The Noctua fans came ready to install with a 4 pin plug on the PWM type and 3pin plug on the FLW type. The fans also came with wire connectors and silicone anti vibration Connectors both with a 6 year warranty. The result was an immediate reduction of around 20dbA in noise withe the 2 new fans however the Noctua fans move around 30% less air the case temperature of the NVR in one location was around 2 degrees C warmer. The only other consideration would be that this successful modification may compromise the NVR warranty if there was an issue during the NVR warranty.
I was hesitant to buy this fan at first because I wondered how much quieter it could actually be than the fan I was using. I was very surprised by how quiet it was! It made absolutely no noise. I had to look at the fan to actually verify that it was really running.
Nice and silent. High performance. I used it to replace 2 noisy fans in a Cisco switch. I needed to do minor modifications to cables (swap to wires), and to a fan (remove about 1mm of plastic on one side, very little, so it doesn't interfere with PCB and case, blades are still not touching PCB tho!), after that is works really nice. Cisco switch shows a fan error, but I just ignore it. Temperature is good, and it is now much silent. Basically totally silent compared to other equipment I have in the room.
Ive been installing these fans inside Solar controllers an RV converters for a long time. Due to their high efficiency, low noise and high reliability, they are perfect for this application. Reducing internal temperature is the best way to increase these expensive electronics lifespan. Highly recommended! Thanks
At first, I didn't believe the 'hype' about these fans being 'silent'. I've used fans for many years now and many of them confess to being quite. These Noctua fans take it to a different level. Moving air is inherently noisy no matter which way you look at it, but those people in R&D need a clap! I've exchanged all my NOISY fans in my 3d printer and now, i could probably run a print job in a library !! The price seems 'steep' for a small 40mm fan, but my word they are outstanding. Also, included in the price you get all the mounting kit you could ever need, along with an abundant array of cables. Well done Noctua.
Noctua fans are the undisputed best. I needed these to replace noisy fans in a NetGear switch.The fans are the right size and spec but the supplied rubber mounting plugs and the supplied screws will not work with the switch as the screw holes on the switch are too small and too close to the edge, so I had to improvise with my own fittings, which is a bit disappointing when these fans are sold as "fit almost every device". The supplied cable crimping connectors for splicing into existing fan cables is a nice idea.
| General | |
| Product Type | Case fan |
| Package Content | Screws, OmniJoin Adaptor Set, extension cable (30 cm), NA-AV3 anti-vibration mounts |
| Width | 4 cm |
| Depth | 4 cm |
