Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 12 - Jul 17
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Noctua NF-A4X20 5V PWM 40x20mm Premium Cooling FanFeaturing advanced aerodynamic design measures such as Flow Acceleration Channels and an AAO frame, the NF A4x20 5V PWM is a PWM enabled 5V variant of Noctuas highly optimised, premium quality quiet 40x20mm fan. The custom designed NE FD3 PWM IC that integrates Smooth Commutation Drive technology and Noctuas reference class SSO2 bearings guarantee superb running smoothness and excellent long term stability. Topped off with modular cabling, the
Featuring advanced aerodynamic design measures such as Flow Acceleration Channels and an AAO frame, the NF-A4x20 5V PWM is a PWM enabled 5V variant of Noctua’s highly optimised, premium quality quiet 40x20mm fan. The custom designed NE-FD3 PWM IC that integrates Smooth Commutation Drive technology and Noctua’s reference class SSO2 bearings guarantee superb running smoothness and excellent long-term stability. Topped off with modular cabling, the OmniJoin™ Adaptor Set and 6 years manufacturer’s warranty, the NF-A4x20 5V PWM is a premium choice for demanding 5V applications that require PWM control.
Being a 5V fan, the NF-A4x20 5V PWM cannot be run at 12V and will be damaged when used with typical 12V power sources such as PC motherboard fan headers
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.
5V PWM version
Many devices such as network or storage solutions use 5 volt 40mm fans with PWM speed control. With the same operating voltage, PWM support and the included OmniJoin™ adaptor set that makes it compatible with proprietary fan headers, the NF-A4x20 5V PWM is ideal for replacing noisy or broken 5V 40mm fans with PWM.
Polarity protection
As many devices using 5V fans feature proprietary connectors, and documentation of the pin alignment may not be available, the fan features an integrated diode for polarity protection. This way, you're on the safe side if you accidentally connect it with reverse polarity.
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.
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.
Stepped Inlet Design
Noctua's Stepped Inlet Design adds turbulence to the influx in order to facilitate the transition from laminar flow to turbulent flow, which reduces tonal intake noise, improves flow attachment and increases suction capacity, especially in space-restricted environments.
Inner Surface Microstructures
With the tips of the fan blades ploughing through the boundary layer created by the Inner Surface Microstructures, flow separation from the suction side of the blades is significantly suppressed, which results in reduced blade passing noise and improved airflow and pressure efficiency.
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.
Custom-designed PWM IC with SCD
Supporting fully automatic PWM speed control, the fan uses Noctua's custom-designed NE-FD3 5V PWM IC that integrates Smooth Commutation Drive (SCD) technology. By providing smoother torque impulses, SCD suppresses PWM switching noises and thus makes the fan quieter at low speeds.
OmniJoin™ adaptor set
Many devices featuring 40mm fans use proprietary fan headers, so the NF-A4x20 comes with Noctua's OmniJoin™ adaptor set. Just cut the original fan's cable, fix it to the adaptor using the supplied 3M Scotchlok™ connectors and you can plug the NF-A4x20 to proprietary fan headers!
Extensive cabling options
The fan's short 20cm primary cable minimises cable clutter in typical applications while the supplied 30cm extension provides extended reach when necessary. Both cables are fully sleeved and a 4-pin y-cable allows the connection of a second fan to the same PWM fan header for automatic control.
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.
6-year manufacturer’s warranty
Noctua fans are renowned for their impeccable quality and outstanding longevity. Like all Noctua fans, the NF-A4x20 features an MTTF of more than 150.000 hours rating and comes with a full 6-year manufacturer’s warranty.
Technical Specifications
Size: 40x40x20 mm
Mounting hole spacing: 32x32 mm
Connector & pin-configuration: 4-pin PWM
Cable length: 20cm + 30cm NA-EC1 extension cable
Bearing: SSO2
Blade geometry: A-Series with Flow Acceleration Channels
Frame technology: AAO (Advanced Acoustic Optimisation)
Rotational speed (+/- 10%): 5000 RPM
Min. rotational speed (PWM, +/-20%): 1100 RPM
Airflow: 9,4 m³/h
Acoustical noise: 14,9 dB(A)
Static pressure: 2,26 mm H₂O
Max. input power: 0,5 W
Max. input current: 0,1 A
Operating voltage: 5 V
Voltage: PWM signal 5 V
MTTF: > 150.000 h
Warranty: 6 years
Package includes:
- Noctua NF-A4X20 5V PWM Cooling Fan
- 4-pin y-cable
- 30cm extension cable
- OmniJoin™ adaptor set
- NA-AV3 anti-vibration mounts
- Fan screws
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.6 ★★★★★
Based on 2151 reviews
Sort
Product Reviews
★★★★★ 5
I love it for my workspace! Hot tea all day
Color: Wood Grain
I love this item. The size is perfect, as I prefer something less bulky for my work desktop. It isn't as fancy as others that has the digital display screen, which is fine by me, because I don't necessarily need that. The knob and different colors that indicate the temperature range works fine. The temperature on this thing works fantastically well for me. Using it on the lowest setting keeps my drink nice and hot in a cold office. I use a heatproof glass teapot with this and its a good fit. It keeps my tea hot throughout the day, so I am able to pour smaller amounts of drink and take my time sipping it throughout the day without worrying that it will get cold. At point I almost forgot that it has an automatic shut-off safety feature when I noticed it was off. So that is a good feature to have. I highly recommend this.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 15, 2026
★★★★★ 4
Requires a very specific mug to be useful.
Color: Black
The hotplate itself gets hot enough on its highest setting where it would burn your finger if you left it one there for more then a couple seconds. However when it come to what mug you can use to transfer that heat to your drink, this WILL NOT work with just any old ceramic, metal or glass mugs. You absolutely need to have a perfectly flat bottom on it. If the center of the bottom of the mug does not make direct contact with the very center of the warmer, it will not transfer heat. So straight way plan of spending another $15 to $20. Amazon has some available with good reviews all be it not a very big selection. I'm giving this 4 stars because the description needs to be very clear about this and its not.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 8, 2026
★★★★★ 5
Great mug warmer with temp control
Color: Black
I replaced a cheap mug warmer with a couple of these for the house, and for almost the same price this is a lot more functional. I really like the temperature control and silicone surface protector. In combination with the carafe below, this has changed my life - no more microwaving coffee all morning.
https://www.amazon.com/GiNT-Stainless-Thermal-Thermos-Retention/dp/B07MW5N7MS
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 10, 2026
★★★★★ 5
Super Satisfied Customer Here!
Color: Gold, Color: Gold
I purchased the gold/black mug warmer. I always spend a good about of money for great coffee products and I take my time to perfect my coffee for my mornings at work. However, I get pulled into urgent meetings and just something urgent and I always leave more than half of my coffee behind. When I come back it’s cold and that’s very disappointing considering the money and time I spent to make it bc I then have to toss it. I don’t believe in microwaves and I refuse to use one. When I found this, I was super excited! It looks perfect at my desk and it works perfect! I would have liked it to be more on the brass gold like my pen holder, but it’s just as pretty! As you can see, my mug had a layer on the bottom and that made me think it may not work well, but it did the job. My coffee was super warm and it got even hotter as I left it there tearing it. I turned it one before making my coffee, so I’m not sure exactly how long it took to warm up but for me, by the time I got back, it was the peg temperature. I highly recommend this to anyone who has the same struggles. No more cold coffees! Thank you!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 21, 2026
★★★★★ 5
Perfect Cold Brew Maker – Durable and Easy to Use
Size: 64 Ounces, Color: Gray
This jar is exactly what I was looking for. The 64oz size is great for making multiple servings and the wide mouth makes it easy to fill and clean. The glass feels sturdy, the lid is truly leakproof, and it’s perfect for cold brew. Simple, reliable, and well-made. Highly recommend!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 24, 2026
recommand products
Sartorius FT-4-303-270 Qualitative & Technical Papers, Smooth/ Grade 3 hw, ⌀ 270 mm 100/Pk.
69.15
Sartorius FT-4-305-320 Qualitative & Technical Papers, Smooth/ Grade 3 m/N, ⌀ 320 mm 100/Pk.
90.60
Sartorius FT-4-305-150 Qualitative & Technical Papers, Smooth/ Grade 3 m/N, ⌀ 150 mm 100/Pk.
38.55
Sartorius FT-4-305-090 Qualitative & Technical Papers, Smooth/ Grade 3 m/N, ⌀ 090 mm 100/Pk.
110.66
Sartorius FT-4-303-500 Qualitative & Technical Papers, Smooth/ Grade 3 hw, ⌀ 500 mm 100/Pk.
142.97