--- product_id: 51055764 title: "Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm" brand: "noctua" price: "R727" currency: ZAR in_stock: true reviews_count: 13 url: https://www.desertcart.co.za/products/51055764-noctua-nf-a4x20-flx-high-performance-quiet-fan-40mm store_origin: ZA region: South Africa --- # >150,000 hours MTTF reliability 5000 RPM max speed Ultra-quiet 14.9 dB(A) Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm **Brand:** noctua **Price:** R727 **Availability:** ✅ In Stock ## Summary > 🌀 Quiet power in a compact package — cool smarter, work better. ## Quick Answers - **What is this?** Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm by noctua - **How much does it cost?** R727 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.za](https://www.desertcart.co.za/products/51055764-noctua-nf-a4x20-flx-high-performance-quiet-fan-40mm) ## 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 - • **Built to Last:** Engineered for >150,000 hours MTTF backed by a 6-year warranty — reliability that keeps your critical systems cool and running. - • **Compact Powerhouse:** Slim 40x40x20mm size fits seamlessly into 1U servers, routers, NAS, and other professional gear without compromise. - • **Whisper-Quiet Operation:** Advanced Acoustic Optimisation and Flow Acceleration Channels ensure near-silent cooling, perfect for noise-sensitive workspaces. - • **Vibration-Free Stability:** Includes anti-vibration mounts and OmniJoin adaptor set for secure, rattle-free installation in any setup. - • **Precision Airflow Control:** Three-speed FLX settings (5000/4400/3700 RPM) let you tailor cooling performance or silence to your exact needs. ## Overview The Noctua NF-A4x20 FLX is a premium 40x40x20mm high-performance fan designed for professional-grade cooling in compact devices like 1U servers, routers, and NAS units. Featuring three adjustable speeds up to 5000 RPM, ultra-low noise levels at 14.9 dB(A), and advanced aerodynamic design, it delivers efficient airflow with whisper-quiet operation. Its robust build ensures over 150,000 hours of reliable service, supported by a 6-year warranty, making it the go-to choice for managers demanding silent, dependable cooling in critical network and storage equipment. ## 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. ## Features - Premium quiet fan, 40x40x20 mm, 12V, 3-pin Molex, 5000/4400/3700 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 | B071J8CZP9 | | Best Sellers Rank | 3,192 in Business, Industry & Science (See Top 100 in Business, Industry & Science) 23 in Thermal Management Products 75 in Fans & Cooling | | Brand | Noctua | | Compatible Devices | Server, Router, NAS, Switch, Video Recorder | | Cooling Method | Air | | Country Of Origin | China | | Customer Reviews | 4.8 4.8 out of 5 stars (2,628) 4.8 out of 5 stars | | Global Trade Identification Number | 09010018100112 | | Included Components | NF-A4x20 FLX | | Item Dimensions L X W X H | 40L x 40W x 20H millimetres | | Item Highlight | High Airflow, Low Noise, 20mm Thick, for PC and Electronics Cooling, 3 Speed Settings 5000/4400/3700rpm 3-Pin | | Item Weight | 50 Grams | | Manufacturer | Noctua | | Manufacturer Part Number | NF-A4x20 FLX | | Max Rotational Speed | 5000 RPM | | Model Number | NF-A4x20 FLX | | Noise Level | 14.9 Decibels | | Number Of Items | 1 | | Number Of Packs | 1 | | Power Connector Type | 3-Pin | | Product Warranty | 6 year manufacturer’s warranty | | Unit Count | 1.0 count | | Voltage | 12 Volts | ## Product Details - **Brand:** Noctua - **Compatible devices:** Server, Router, NAS, Switch, Video Recorder - **Cooling method:** Air - **Global Trade Identification Number:** 09010018100112 - **Maximum rotational speed:** 5000 RPM - **Noise level:** 14.9 Decibels - **Power connector type:** 3-Pin - **Product dimensions:** 40L x 40W x 20H millimetres - **Voltage:** 12 Volts ## Images ![Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm - Image 1](https://m.media-amazon.com/images/I/71lyRpVR4OL.jpg) ![Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm - Image 2](https://m.media-amazon.com/images/I/81abh0+LmWL.jpg) ![Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm - Image 3](https://m.media-amazon.com/images/I/71NYZ3JQcOL.jpg) ![Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm - Image 4](https://m.media-amazon.com/images/I/71Ywc8LceeL.jpg) ![Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm - Image 5](https://m.media-amazon.com/images/I/61xqdXxj1uL.jpg) ## Available Options This product comes in different **Size Name** options. ## Questions & Answers **Q: How can I use this fan with a 2 pin connection. I’ve just received it only to find my connection is 2 pin. Doh!** A: Black is (-), red is (+) and yellow is just the probe. You disconnect/cut the yellow one and you have two active wires. **Q: You replaced Hikvision nvr fan with Noc 40x20. What voltage did u use 12 or 5?** A: This Noctua fan is rated 5V and this is the voltage to use. **Q: has anyone tried this in a dan a4 case as a top fan? And would it be worth doing?** A: I don't know where it would fit at the top of the A4, as the riser cables and psu cable take up the space, there might just be enough space on the GPU side. I have this fan zip-tied to the CPU side panel. **Q: Good day, when will this item be back in stock again?** A: it is https://www.amazon.co.uk/gp/offer-listing/B009NQLT0M/ref=dp_olp_new_mbc?ie=UTF8&condition=new ## Customer Reviews ### ⭐⭐⭐⭐⭐ I’m fan ! *by on Reviewed in the United Kingdom 17 July 2026* Very good quality, super quiet and efficient, very good value with every connector included . ### ⭐⭐⭐⭐⭐ Excellent low noise replacement for OEM fans in network switch. *by on Reviewed in the United Kingdom 7 October 2025* I bought a POE switch (Drayek 1282 to be exact) - I had plans on mounting the switch to the wall behind my desk. I work in data centres a lot, so it shouldn't have surprised how loud the thing was. I took a gamble and bought a couple of these fans. The swap out was very easy - most PC kit will want a 12v fan (in case you were wondering to go with the 5v or 12v variant). The fans ship with everything you could need. My OEM fans connected to a 2 pin header on the main board. I cut the connectors from the old fans and used the included "OnmiJoin adaptor kit" to hook the new Noctua fans up to the original connectors. Again very easy. Mounting the fans in the chassis was easy as well.On power up the drop in noise was significant. Degrees of magnitude quieter. I ran for a day to check switch temperatures were staying low - all good. With that working well, I cracked open the switch again and added the (included) low noise adaptor - this just slows the fan RPM down a bit to reduce the fan noise. Again noticeable difference. Am now at the stage where the switch is under my desk and I can't hear it above the background noise anymore. Bearing in mind that with the OEM fans the noise levels were at the "extremely annoying " level on the other side of a closed door. Very happy - just wish I'd videoed the whole process. ### ⭐⭐⭐⭐⭐ Much quieter Omada switch *by on Reviewed in the United Kingdom 2 October 2026* Made a massive difference to the sound of a new Poe switch.Noctua always top quality and quiet. ## Frequently Bought Together - Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown) - Noctua NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown) --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.za/products/51055764-noctua-nf-a4x20-flx-high-performance-quiet-fan-40mm](https://www.desertcart.co.za/products/51055764-noctua-nf-a4x20-flx-high-performance-quiet-fan-40mm) --- *Product available on Desertcart South Africa* *Store origin: ZA* *Last updated: 2026-10-21*