---
product_id: 47568525
title: "NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM)"
brand: "noctua"
price: "R$276"
currency: BRL
in_stock: true
reviews_count: 13
category: "Noctua"
url: https://www.desertcart.com.br/products/47568525-nf-a4x20-flx-computer-case-fan-cooling-components-computer-case
store_origin: BR
region: Brazil
---

# 5000 RPM max speed Ultra-quiet 14.9 dB(A) Includes anti-vibration mounts & adaptors NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM)

**Brand:** noctua
**Price:** R$276
**Availability:** ✅ In Stock

## Summary

> 🌀 Silence meets power: The ultimate compact cooling upgrade

## Quick Answers

- **What is this?** NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) by noctua
- **How much does it cost?** R$276 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.com.br](https://www.desertcart.com.br/products/47568525-nf-a4x20-flx-computer-case-fan-cooling-components-computer-case)

## Best For

- noctua enthusiasts

## Why This Product

- Trusted noctua brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Plug & Play Versatility:** OmniJoin adaptor set ensures seamless compatibility with proprietary headers
- • **Precision Cooling Power:** Up to 5000 RPM for optimized airflow in compact spaces
- • **Whisper-Quiet Operation:** Advanced acoustic design keeps noise below 15 dB—work in peace
- • **Vibration-Free Stability:** Integrated anti-vibration pads minimize noise and extend fan life
- • **Customizable Speed Settings:** Three RPM modes via Low-Noise Adaptors for tailored performance

## Overview

The Noctua NF-A4x20 FLX is a premium 40x40x20mm computer case fan engineered for high-performance cooling in tight spaces. Featuring a max speed of 5000 RPM, ultra-quiet operation at just 14.9 dB(A), and advanced aerodynamic technologies like Flow Acceleration Channels and SSO2 bearings, it delivers efficient airflow with minimal noise. The FLX version offers three speed settings via included Low-Noise Adaptors, plus anti-vibration mounts and an OmniJoin adaptor set for easy installation in network equipment, desktops, and specialized devices. Backed by a 6-year warranty, it’s the go-to choice for professionals demanding silent, reliable cooling.

## Description

Product description Featuring advanced aerodynamic design measures such as Flow Acceleration Channels and Noctua’s AAO frame, the NF-A4x20 is a highly optimised, premium-quality quiet fan in size 40x20mm. The FLX version provides 5000/4400/3700rpm speed settings via the supplied Low-Noise Adaptors and includes the OmniJoin Adaptor Set for easy connection to proprietary fan headers. Its superb running smoothness, reference-class SSO2 bearing and Noctua’s trusted premium quality make it an elite choice for the highest demands. 40x20mm size Compared to Noctua’s award-winning NF-A4x10, the NF-A4x20 is twice as thick, which allows for increased static pressure performance and makes the NF-A4x20 ideal for demanding applications with high flow resistance. Flow Acceleration Channels The NF-A4x20 impeller features suction side Flow Acceleration Channels. By speeding up the airflow at the crucial outer blade regions, this measure reduces suction side flow separation and thus leads to better efficiency and lower vortex noise. SSO2 Bearing The NF-A4x20 features the further optimised second generation of Noctua's renowned, time-tested SSO bearing. With SSO2, the rear magnet is placed closer to the axis to provide even better stabilisation, precision and durability. Integrated Anti-Vibration Pads Integrated Anti-Vibration Pads made from extra-soft silicone minimise the transmission of minute vibrations while maintaining full compatibility with all standard mounting systems and fan clips used on heatsinks. Scope of delivery NA-RC10 Low-Noise Adaptor (L.N.A) NA-RC12 Ultra-Low-Noise Adaptor (U.L.N.A) NA-EC2 30cm extension cable OmniJoin adaptor set 4x NA-AV3 anti-vibration mounts Fan screws AAO frame Noctua's AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design and Inner Surface Microstructures, both of which further refine the fan's performance/noise efficiency.

Review: Perfect for network switch fan replacement projects - Noctua is an amazing company - I purchased an unmanaged 5 port, 10gbe / 100gbs network switch to put in my makeshift networking closet. Closet is about 6 feet from my work station. Switch works GREAT, but has a 40mm fan that is legit 40db loud on the tech sheet for it but more like 50db in real life which is like having a conversation with a person loud. To remedy the issue, I purchased this fan. The fan itself is of the high quality and acumen for brown color tones one would expect from Noctua, so I'm not even going to touch on that. What is the most amazing about this purchase is everything else it comes with the kit and how Noctua caters to the primary use case for their customers here. My OEM fan has a 2 pin connector to the PCB. Noctua includes a converter so you can splice the OEM 2 pin together with the converter that plugs into the 3 pin coming from the fan. In addition, Noctua provides 3 tool-less (mostly) connectors for the splice. When you crush them down it squirts some kind of non conductive oil into the connections to protect it from water and dust. Made by 3M, but nevertheless a WELL thought out solution to include for their customers. Running at 4000+ rpm is extremely unnecessary for this network switch & since silence is the name of the game for me a way to reduce RPM without implementing a PWM controller in my limited space configuration. Another whammy from Noctua for this problem. Two RPM cables are included that step down the rpm without the need for a separate controller. I used the ultra low noise cable. It reduce the noise some, but the fan itself made such a difference that alone should do the trick for most people. I've purchased a lot of PC components and networking hardware over the years. Not sure I've ever felt like a company thought this much about their customer for something that costs such a small amount of money. The time and frustration they saved me is immeasurable and priceless. Good job Noctua :-)
Review: Fits the Icom IC-2730B - The IC-2730 is a great radio, but it has a fan that comes on as soon as you transmit in high power mode. Then it stays on for a minute or more even if you only keyed up for a second or so. And the fan is loud! In medium power mode, it takes 10 or 15 seconds for the fan to come on and then it stays on for a while. This Noctua fan fits the radio perfectly and is so quiet that it is hard to tell if it is running or not. That is no exaggeration. Installation is easy but requires that the connector from the old fan be spliced onto the wires of the new fan. The new fan comes with solderless connectors to do this, but they are too big, so I just cut the wires and spliced them, soldering the connections. Just ignore the yellow wire from the fan; it is not needed in this radio. Note that the fan blows into the radio, not out. This easy modification makes a great radio better.

## Features

- Premium quiet fan, 40x40x20 mm, 12V, 3-pin Molex, 5000/4400/370 RPM, max. 14.9 dB(A), >150,000 h MTTF
- Award-winning A-series design with Flow Acceleration Channels and Advanced Acoustic Optimisation frame for superior quiet cooling performance
- 40x20mm size ideal for 1U applications or replacing fans in network and storage equipment (routers, switches, NAS etc.) or other devices such as DVRs
- 3-pin FLX version provides 5000/4400/3700rpm speed settings via Low-Noise Adaptors to fine-tune the fan for maximum airflow or near-silent operation
- Includes anti-vibration mounts, fan screws, extension cable and OmniJoin adaptor set for connecting the fan to proprietary fan headers

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B072JK9GX6 |
| Air Flow Capacity | 9.4 Cubic Meters Per Hour |
| Best Sellers Rank | #94 in Computer Case Fans |
| Brand | Noctua |
| Brand Name | Noctua |
| Compatible Devices | Desktop |
| Cooling Method | Air |
| Customer Reviews | 4.8 out of 5 stars 2,511 Reviews |
| Included Components | 1 |
| Item Dimensions L x W x H | 1.57"L x 1.57"W x 0.79"H |
| Manufacturer | Noctua |
| Material Type | Fibre-glass reinforced PBT |
| Maximum Rotational Speed | 5000 RPM |
| Model | NF-A4x20 FLX |
| Noise Level | 14.9 Decibels |
| Part Number | NF-A4x20 FLX |
| Power Connector Type | 3-Pin |
| Product Dimensions | 1.57"L x 1.57"W x 0.79"H |
| UPC | 841500110116 |
| Unit Count | 1.0 Count |
| Voltage | 12 Volts |
| Warranty Description | 6 year manufacturer’s warranty |

## Product Details

- **Air Flow Capacity:** 9.4 Cubic Meters Per Hour
- **Brand:** Noctua
- **Compatible Devices:** Desktop
- **Cooling Method:** Air
- **Material:** Fibre-glass reinforced PBT
- **Maximum Rotational Speed:** 5000 RPM
- **Noise Level:** 14.9 Decibels
- **Power Connector Type:** 3-Pin
- **Product Dimensions:** 1.57"L x 1.57"W x 0.79"H
- **Voltage:** 12 Volts

## Images

![NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) - Image 1](https://m.media-amazon.com/images/I/71lyRpVR4OL.jpg)
![NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) - Image 2](https://m.media-amazon.com/images/I/81abh0+LmWL.jpg)
![NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) - Image 3](https://m.media-amazon.com/images/I/71NYZ3JQcOL.jpg)
![NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) - Image 4](https://m.media-amazon.com/images/I/71Ywc8LceeL.jpg)
![NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) - Image 5](https://m.media-amazon.com/images/I/61xqdXxj1uL.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: Whats the cfm of this fan?**
A: The output, converted from 9.4 m3/h is just 5.5 cfm, very low indeed.

**Q: 14.9dba at what speed?**
A: 5000rpm.

**Q: How many dB is this fan?**
A: 14.9db(a)

**Q: What is the mtbf. How many hours of life can I expect from one of these?**
A: Not sure about the Mtbf, but i purchased 2 of this in Jan 2020, and they have been running 24/7 till now with no problems. Installed them in my 2 poe+ switches

## Customer Reviews

### ⭐⭐⭐⭐⭐ Perfect for network switch fan replacement projects - Noctua is an amazing company
*by P***K on November 15, 2024*

I purchased an unmanaged 5 port, 10gbe / 100gbs network switch to put in my makeshift networking closet. Closet is about 6 feet from my work station. Switch works GREAT, but has a 40mm fan that is legit 40db loud on the tech sheet for it but more like 50db in real life which is like having a conversation with a person loud. To remedy the issue, I purchased this fan. The fan itself is of the high quality and acumen for brown color tones one would expect from Noctua, so I'm not even going to touch on that. What is the most amazing about this purchase is everything else it comes with the kit and how Noctua caters to the primary use case for their customers here. My OEM fan has a 2 pin connector to the PCB. Noctua includes a converter so you can splice the OEM 2 pin together with the converter that plugs into the 3 pin coming from the fan. In addition, Noctua provides 3 tool-less (mostly) connectors for the splice. When you crush them down it squirts some kind of non conductive oil into the connections to protect it from water and dust. Made by 3M, but nevertheless a WELL thought out solution to include for their customers. Running at 4000+ rpm is extremely unnecessary for this network switch & since silence is the name of the game for me a way to reduce RPM without implementing a PWM controller in my limited space configuration. Another whammy from Noctua for this problem. Two RPM cables are included that step down the rpm without the need for a separate controller. I used the ultra low noise cable. It reduce the noise some, but the fan itself made such a difference that alone should do the trick for most people. I've purchased a lot of PC components and networking hardware over the years. Not sure I've ever felt like a company thought this much about their customer for something that costs such a small amount of money. The time and frustration they saved me is immeasurable and priceless. Good job Noctua :-)

### ⭐⭐⭐⭐⭐ Fits the Icom IC-2730B
*by E***N on September 25, 2025*

The IC-2730 is a great radio, but it has a fan that comes on as soon as you transmit in high power mode. Then it stays on for a minute or more even if you only keyed up for a second or so. And the fan is loud! In medium power mode, it takes 10 or 15 seconds for the fan to come on and then it stays on for a while. This Noctua fan fits the radio perfectly and is so quiet that it is hard to tell if it is running or not. That is no exaggeration. Installation is easy but requires that the connector from the old fan be spliced onto the wires of the new fan. The new fan comes with solderless connectors to do this, but they are too big, so I just cut the wires and spliced them, soldering the connections. Just ignore the yellow wire from the fan; it is not needed in this radio. Note that the fan blows into the radio, not out. This easy modification makes a great radio better.

### ⭐⭐⭐⭐⭐ A fan that lives up to Noctua’s reputation
*by L***N on January 12, 2019*

I recently upgraded the case for my computer. The new case had much quieter fans than my old one. Happy as a peacock, I set about using it, only to be disturbed by a high pitched whine that quickly got on my nerves. A little investigation and I discovered that the stock 40mm fan that helped cool a component on my motherboard was the culprit. So I went looking for a replacement. Enter the Noctua fan. I was familiar with Noctua from research I’d done about CPU cooler fans a few years ago. Their reputation is very good. That inspired my purchase of this fan over other less expensive brands. I wasn’t disappointed. This fan is quiet. There is very little noise other than the sound of air moving through it. Even that is minimal. Obviously, that is exactly what I was looking for, so it fits the bill perfectly. I wanted a fan that wouldn't disturb the peace. This one is quiet as a mouse. Overview: The fan comes with a standard 3 pin connector that is common on many motherboards and electronics. It also has an assortment of additional items in the box. This includes a short extension cable, low noise adapters that reduce the speed of the fan and 4 omnijon clips , so you can easily remove the included 3 pin connector and connect a new one if needed. A set of case screws and anti-vibration mounts are also included in the box. The fan itself has silicon pads on the corners to help cut down on vibration. Unlike other reviewers, I had no issue with them falling off. I did not use any of the mounting options provided in the box as I simply used the mounting solution my mother board already provided. I suspect that the anti-vibration mounts would be one time use. They’re shaped like Christmas tree clips and would probably get shredded when removed. Another bonus is that it has a nicely presented set of instructions explaining how to use the adapters and silicon mounts. Bottom line: The packaging for this fan is crazy. It comes in a double book fold cardboard box with a molded plastic tray. I guess they’re trying to give the impression of quality with the packaging, but it really seems like overkill for a product that cost only 14 dollars. Noctua wants its customers to feel like they got a quality product by providing one and packaging it like one. Well, it worked. This is a great little fan.

## Frequently Bought Together

- Noctua NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM)
- Noctua NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown)
- Noctua NF-A4x20 PWM, Premium Quiet Fan, 4-Pin (40x20mm, Brown)

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*Product available on Desertcart Brazil*
*Store origin: BR*
*Last updated: 2026-05-08*