Noctua
NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) (Pack of 2)
*Price sourced from Amazon.com. Last updated 2026-07-07. Price and availability subject to change.
Bottom line: The NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) (Pack of 2) is a niche pick — read recent reviews before buying in the cooling & fans category, priced around $31.90. Read recent reviews carefully before committing.
Description
SpecPicks Verdict
SpecPicks classifies Noctua NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer… as a niche pick — read recent reviews before buying in the cooling & fans category, based on our editorial and benchmark analysis and our ranking model that weights rating × review-volume × price-fit. Noctua's positioning sits within the broader category mid-tier. Use the Compare tool to put it side-by-side with two or three close alternatives before clicking through to Amazon.
Common buyer scenarios for cooling & 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
- ✓ The information below is per-pack only
- ✓ 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
- The information below is per-pack only
- 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 |
| Material | Plastic, Rubber |
| Dimensions | 40x40x20 mm |
| Unit Count | 2.0 Count |
| Noise Level | 14.9 Decibels |
| Part Number | NF-A4x20 FLX |
| Material Type | Plastic, Rubber |
| Cooling Method | forced air |
| Number of Packs | 2 |
| Vibration/Rumble | Yes |
| Compatible Devices | Desktop, Graphic Cards, Projector, Receiver, Transmission Coolers |
| Power Connector Type | 3-Pin |
| Maximum Rotational Speed | 5000 RPM |
Ready to buy?
Noctua NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM) (Pack of 2) is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-07-07. Price and availability subject to change.
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