Joseph Grenny, Ron McMillan, Al Switzler, Kerry Patterson, Laura Roppe(Reader)&2moreFormat:Audio CD
Noctua
Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm
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*Price sourced from Amazon.com. Last updated 2026-08-28. Price and availability subject to change.
Bottom line: The Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm is a niche pick — read recent reviews before buying in the cpu coolers & fans category, priced around $15.95. Compare close alternatives before committing.
SpecPicks Verdict
SpecPicks scored Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm using a rating × review-volume × price-fit model applied to our editorial and benchmark analysis across the cpu coolers & fans category. Noctua's cpu coolers & fans lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Mixed or limited buyer feedback at this price point — focus your evaluation on recent reviews that specifically address build quality and long-term reliability, and shortlist one or two close alternatives before deciding.
Common buyer scenarios for cpu coolers & fans of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.
Pros & Cons
Pros
- ✓ Backed by Noctua's warranty and support channels
- ✓ Ships via Amazon with Prime eligibility and the standard returns policy
Cons
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified
Key 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
Full Specifications
| Brand | Noctua |
|---|---|
| Model | NF-A4x20 FLX |
| Voltage | 12 volts |
| Material | Fibre-glass reinforced PBT |
| Dimensions | 40x40x20 mm |
| Unit Count | 1 Count |
| Noise Level | 14.9 db |
| Part Number | NF-A4x20 FLX |
| Material Type | Fibre-glass reinforced PBT |
| Cooling Method | Air |
| Number of Packs | 1 |
| Vibration/Rumble | Yes |
| Air Flow Capacity | 9.4 cubic meter per hour |
| Compatible Devices | Desktop |
| Included Components | 1 |
| Power Connector Type | 3-Pin |
| Warranty Description | 6 year manufacturer’s warranty |
| Maximum Rotational Speed | 5000 rpm |
| Item Dimensions L x W x H | 1.57"L x 1.57"W x 0.79"H |
Ready to buy?
Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm is sold on the used and vintage market, where eBay carries the live inventory — Amazon does not stock this part. Prices and condition vary by seller and move in real time, so we link the live listing rather than quote a cached price. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-08-28. Price and availability subject to change.
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