heading

The NF-A9 is a highly optimised, premium quality quiet 92mm fan. Featuring Noctua’s AAO (Advanced Acoustic Optimisation) frame as well as sophisticated aerodynamic design measures such as Flow Acceleration Channels, the NF-A9 further improves the renowned quiet cooling performance of the award-winning NF-B9. The PWM version sports Noctua’s custom designed NE-FD1 IC for fully automatic speed control via 4-pin fan headers and comes with a Low-Noise-Adaptor to reduce the maximum speed during PWM control from 2000 to 1550rpm. Its superb running smoothness, reference-class SSO2 bearing and Noctua’s trusted premium quality make it an elite choice for the highest demands.

Details
Succeeding the award-winning NF-B9

Succeeding the award-winning NF-B9

Noctua's NF-B9 fan has become a default-choice among PC enthusiasts looking for a premium quality quiet 92mm fan. Thanks to its thoroughgoing aerodynamic optimisations, the NF-A9 provides higher static pressure and an even better airflow/noise ratio than its much acclaimed predecessor.
Flow Acceleration Channels

Flow Acceleration Channels

The NF-A9 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

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

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

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

Integrated anti-vibration pads made from extra-soft silicone minimise the transmission of minute vibrations while maintaining full compatibility with all standard screws and other mounting systems.
SSO2 Bearing

SSO2 Bearing

The NF-A9 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.
Custom-designed PWM IC with SCD

Custom-designed PWM IC with SCD

Supporting fully automatic PWM speed control, the NF-A9 PWM uses Noctua's novel, custom-designed NE-FD1 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.
Low-Noise Adaptor

Low-Noise Adaptor

The NF-A9 PWM is supplied with a (L.N.A.) that reduces the maximum fan speed from 2000 to 1550rpm. The L.N.A. can be used either to run the fan at a fixed speed of 1550rpm or to cap the maximum speed when using automatic PWM control.
Extensive cabling options

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 NF-A9 PWM fan to the same PWM fan header for automatic control.
6-year manufacturer’s warranty

6-year manufacturer’s warranty

Noctua fans are renowned for their impeccable quality and outstanding longevity. Like all Noctua fans, the NF-A9 features an MTTF of more than 150.000 hours rating and comes with a full 6-year manufacturer’s warranty.
NF-A9 PWM
FAN Specification
Size
92x92x25 mm
Mounting hole spacing
82,5x82,5 mm
Connector
4-Pin PWM
Bearing
Blade Geometry
Rotational Speed (+/- 10%)
2000 RPM
Rotational Speed with L.N.A. (+/- 10%)
1550 RPM
Min. Rotational Speed (PWM, +/-20%)
400 RPM
Acoustical Noise
22,8 dB(A)
Acoustical Noise with L.N.A.
16,3 dB(A)
Static Pressure
2,28 mm H₂O
Static Pressure with L.N.A.
1,53 mm H₂O
Max. Input Power
1,2 W
Max. Input Current
0,1 A
Voltage
12 V
MTTF
> 150.000 h
Scope of Delivery
  • Low-Noise Adaptor (L.N.A.)
  • 4-Pin Y-Cable
  • 30cm Extension Cable
  • 4 Vibration-Compensators
  • 4 Fan Screws
Warranty
6 years
NF-A9 PWM
A-Series fans
14.05.2016 // Vmodtech.com
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NF-A9 PWM Review

วันนี้ในการทดสอบผมลองต่อทดสอบกับเมนบอร์ดโดยตรงครับ โดยผมวัดแรงลมนี่โอเคเลยครับสำหรับ Airflowแม้จะเป็นพัดลมตัวเล็กๆแต่แรงลมนี่หายห่วงครับเย็นจริงๆแต่ตามที่สเปกเคลมไว้จะอยู่ที่ 78,9 m³/h ครับ ส่วนถ้าใช้งานกับระบบ L.N.A.จะอยู่ที่ 62,6 m³/h ครับ ในส่วนของเสียงรบกวนอันนี้ต้องบอกเลยครับของเค้าเงียบจริงๆ ซึ่งผมได้หยิบมาฟังข้างๆหูนี่ก็เบามากๆเลยครับเงียบมากจริงๆสมกับที่ฟีเจอร์ที่ชูจุดเด่นเรื่องเสียงรบกวนครับ จุดเด่นอีกอย่างก็คือตัวยางทั้ง 4มุมกันกระแทกที่ช่วยซัพแรงและลดเสียงรบกวนได้เป็นอย่างดีครับ
Test verdict: "ก็มาถึงบทสรุปนะครับสำหรับการทดสอบ Noctua NF-A9 PWM ที่ วันนี้ถือว่าทำประสิทธิภาพได้ดีมากเลยครับทั้งในเรื่องของความแรงของพัดลมที่แรงดีจริงๆรวมไปถึงเสียงรบกวนที่ทำออกมาได้สวนทางกับความแรงของพัดลมที่เรีกได้ว่าเงียบจริงๆ กับดีไซน์ที่เน้นเอกลักษณ์ของยี่ห้อ Noctua ในโทนสีครีมตัดน้ำตาลก็ดูดีสวยงามไปอีกแบบครับ แม้ว่าตัดพัดลมจะไม่ได้มีแสงสีอะไรมาให้แต่มองดูรายละเอียดของงานแล้วถือว่าเนี๊ยบมากครับ ในส่วนของอุปกรณ์พวกสายเชื่อมต่อต่างๆก็มีมาให้แบบครบครันครับทั้งสายต่อพ่วง ต่อแยก หรือแม้กระทั่งสายต่อระบบ Low-Noise Adaptor ที่ช่วยเน้นเสียงรบกวนที่เงียบจริงๆ ถือได้ว่าเป็นพัดลมขนาด 92mm ที่เน้นประสิทธิภาพการใช้งานที่ครบครันเหมาะกับท่านทีกำลังมองหาพัดลมประสิทธิภาพเยี่ยมที่ทั้งแรงและเงียบไว้ใช้งานผมมองว่า Noctua NF-A9 PWM ตัวนี้น่าสนใจเป็นอย่างมากครับ โดยราคาวางจำหน่ายอยู่ประมาณ 5XX บาทไทยครับ สำหรับวันนี้ผมก็ขอตัวลาไปก่อน สวัสดีครับ" (Vmodtech.com)
04.04.2016 // ITNdaily.ru
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NF-A9 PWM Review

С одним вентилятором на борту Noctua NH-D9L способен отвести пыл от Intel Core i5-6600K на 4900-5000 МГц. Оптимальным и относительно холодным вариантом является показатель в 4700-4800 МГц. Пропеллер при этом не работает на максимальной скорости.
Test verdict: "Noctua NH-D9L и вентилятор Noctua NF-A9 PWM оставили исключительно положительные впечатления, с такими продуктами приятно работать. Рекомендуем не обходить стороной данные устройства, если такая возможность существует." (Евгений Никифоров, ITNdaily.ru)
04.02.2016 // SmallFormFactor.net
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NF-A9 PWM Review

All in all, these products are well built, well designed, and are able to achieve specs that by-and-large merit the premium price asked of them. None of the tested fans exhibited loud operation, and the included accessories ensured that the fans can be used in many different systems.
Test verdict: "It is typical for high-end or “luxury” goods to embrace a brand, style, or ethos, and Noctua does precisely that with their distinctive color scheme. The rest comes down to performance, though, and while you’ll pay top dollar to install a Noctua fan in your build, we’re hard-pressed to imagine how anyone will find themselves disappointed." (John Morrison, SmallFormFactor.net)
02.11.2015 // Hardaily.com
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NF-A9 PWM Review

Los ventiladores Serie A de Noctua están recomendados por Hardaily como ventiladores suplementarios (versiones no PWM), sustitutos de ventiladores más modestos o viejos para lograr mejor ventilación. Las versiones PWM son altamente recomendadas por Hardaily como sustitutos en los disipadores o radiadores y para que tengan autocontrol, ya que son los más potentes también. Todos ellos son perfectamente válidos para torres, servidores, para disipadores o incluso radiadores, siempre que sean compatibles con las medidas estandarizadas de 4 8 y 9cm. Todos estos ventiladores de Noctua son de los más duraderos y resistentes del mercado.
Test verdict: "Estos productos son prácticamente perfectos." (Raul Planelles, Hardaily.com)
02.10.2015 // BUG 10/2015
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NF-A9 PWM Review

Hladnjake smo testirali na Core i7-5960X procesoru na taktu od 2,8 GHz i naponu od 0,95 V. Riječ je o osmojezgrenoj mrcini pa nismo željeli pretjerivati s grijanjem. Oba hladnjaka isprobali smo s jednim i dva ugrađena ventilatora. U slučaju NH-D9L, dodatni ventilator je upuhivao svježi zrak, dok je kod NH-U9S dodatni ventilator izvlačio topli zrak iz hladnjaka. Testirane su dvije brzine vrtnje - maksimalna koja kod NF-A9 PWM ventilatora iznosi 2.000 rpm te automatska koju je podesio UEFI Asusove X99 Sabertooth ploče. Na automatskim postavkama brzina ventilatora je varirala između 1.200 i 1.400 rpm i pri ovom broju obrtaja oni su praktički nečujni. Pri maksimalnih 2.000 rpm situacija se mijenja i buka postoji, no prema našem mišljenju, sasvim je prihvatljiva, pogotovo ako imamo na umu da je naše testiranje izvedeno na otvorenom stolu, bez kućišta da blokira zvukove.
Test verdict: "Performanse hladnjaka su, s obzirom na njihove gabarite, izvrsne. Pod time podrazumijevamo da će bez problema hladiti većinu procesora koji su trenutno na tržištu, čak i ako se odlučite na overklokiranje." (Denis Arunović;, BUG BUG 10/2015)
26.06.2015 // TugaReviews.com
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NF-A9 PWM Review

Como é habitual a Noctua apresentou-nos excelentes ventoinhas para qualquer tipo de configuração, desde da qualidade de construção até a performance e não esquecendo os acessórios que completam este produto, as ventoinhas Noctua são algo que os entusiastas e até o utilizador comum devem ter em pensamento quando quiserem qualidade e performance até ao ultimo milímetro. Juntando toda a nova tecnologia, a Noctua obteve excelentes resultados e isso está a olhos vistos, a marca é conhecida por ser eximia nos seus produtos, e podemos comprovar isso ao testar estas excelentes ventoinhas.
Test verdict: "Para finalizar só me resta dar a pontuação que estes excelentes produtos merecem, mais uma vez, a Noctua arrecada mais uma vez o ouro devido a sua excelente qualidade e eficácia." (Napoleão Silva, TugaReviews.com)
26.05.2015 // Tweak.dk
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NF-A9 PWM Review

- Rigeligt med tilbehør
- Solid konstruktion
- God ydeevne
- God pris
Test verdict: "Endnu en gang har Noctua leveret varen. De har modificeret og moderniseret en allerede god blæser til at blive om muligt endnu bedre. Denne blæser er blevet forbedret på flere områder, både når det gælder ydelse kontra støjforholdet, nyt og forbedret kugleleje og tilbehør. Alt i alt en rigtig god blæser, som flytter en masse luft uden at larme som en flyvemaskine." (Kim Monberg, Tweak.dk)
10.05.2015 // PC Ekspert
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NF-A9 PWM Review

Kvaliteta materijala i izrade je nešto na što Noctua posebno pazi a to se odrazilo i na ove nove modele. Performanse svih modela su u skladu s onime što deklarira proizvođač i kod Noctue se dobiva točno ono što se i plaća. PWM hladnjaci su po običaju na maksimalnom broju okretaja malo čujniji, no performanse se ne gube nimalo uz upotrebu L.N. adaptera pri čemu se buka ipak dosta smanji.
Test verdict: "Sve u svemu, Noctua uspješno nadograđuje svoj lineup i kupci će kao i uvijek biti vrlo zadovoljni." (Krešimir Matanović, PC Ekspert)
11.03.2015 // OverclockersClub.com
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NF-A9 PWM Review

Noctua is always striving to create a better balance between noise and performance. Noctua is always pressing forward and advancing the engineering behind the products released. If you ask anyone who has quiet, high performance fans for computing, Noctua is going to be on the tip of the tongue. I believe Noctua will continue to strive for perfection by releasing new products. These fans are just a set of the many that have come before and the many that will continue to be released.
Test verdict: "If you want less sound humming from your computer case and better cooling, look no further. Even with their size, these fan models with their high static pressure are up to the challenge. As with all of its products, these fans come with a six year warranty, which is longer than some fans last all together." (Allen Woo, OverclockersClub.com)
10.03.2015 // HardZone.es
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NF-A9 PWM Review

Noctua sigue siendo Noctua, y la calidad de sus productos la mejor. La verdad es que no tienen prácticamente ningún inconveniente si obviamos el apartado estético, algo que siempre ha sido criticado por sus usuarios.
Test verdict: "La calidad de los materiales es la mejor, su funcionamiento impecable y su precio decente para lo que ofrece (alrededor de 16 euros). No podemos hacer otra cosa que recomendarlos para cualquier aplicación que se desee." (Rodrigo Alonso, HardZone.es)

Installation Manual (PDF)

Information Sheet (PDF)

Can I paint my Noctua fan in order to change its color?

Since even small variations in the layer of paint can lead to an imbalance of the impeller, resulting in vibrations, higher noise levels, increased stress on the bearing and thus reduced lifespan, we do not recommend painting the fan. Please note that for the reasons stated above, painting the fan will void your warranty.

What pin configuration do Noctua 12V fans use?

All Noctua fans feature the standard pin-configurations set out in the Intel and AMD specifications. These standard pin-configurations are used on most mainboards and fan controllers today:

pin configuration

How can I find out the direction of airflow and sense of rotation?

When looking at the fan so that the circular sticker with the Noctua logo is facing you, the direction of airflow is towards you and the sense of rotation is clockwise:

P14

The supplied y-cable is missing a wire at one of the two connectors, is it faulty?

No. As mainboards can process only one rpm-signal per fan header, it would cause problems if the cable transmitted rpm-signals of both fans. For this reason, one of the two connectors does not have an rpm wire and only the fan on the other connector will transmit an rpm signal. Automatic speed control of both fans will work independently from the second fan’s rpm signal.

I get a CPU fan error despite the fan is running!

Some mainboards display a CPU fan error when the fan speed falls below a certain threshold, e.g. 900rpm. If you want to run the fan below this speed (e.g. using the supplied U.L.N.A.), please adjust the threshold in the BIOS or disable CPU fan error warning.

How should I clean my Noctua fan?

Fans inside computer cases tend to accumulate dust over longer periods of usage. In order to maintain maximum performance, please clean your fans regularly using a duster, slightly moist tissue or canned air. Please be careful not to use too much force in order to prevent any damage to the fan. Please do not use a vacuum cleaner as this may apply excessive force to the fan and do not put the fan under running water as water residues inside the motor may lead to short circuits.
In order to ensure flawless operation over many years of usage, Noctua’s premium grade SSO bearings are fully sealed to prevent the entering of fine dust particles. Please note that the fan is not designed to be taken apart by the user. Removing the impeller from the frame will break the sealing of the bearing and results in a loss of warranty.

Can I disassemble my fan for cleaning (or other purposes, e.g. painting)?

In order to ensure flawless operation over many years of usage, all Noctua fans come with a premium grade SSO bearing, which is fully sealed to prevent the entering of fine dust particles. Please note that the fan is not designed to be taken apart by the user. Removing the impeller from the frame will break the sealing of the bearing and results in a loss of warranty.

It is thus recommended to clean your fans using a duster, slightly moist tissue or canned air. Please be careful not to use too much force in order to prevent any damage to the fan. Please don’t use a vacuum cleaner as this may apply excessive force to the fan.

Can I run 4-pin PWM fans on 3-pin fan headers?

PWM fans come with a 4-pin connectors for fully automatic speed control via your mainboard’s 4-pin PWM fan headers. Please note that 4-pin fans can also be connected to your mainboard’s 3-pin fan headers though. When connected to 3-pin fan headers, the fan will run at full speed (unless the mainboard supports voltage based speed control).

How can I check if my 4-pin fan header supports PWM?

Some mainboards feature 4-pin fan headers that actually don‘t use a PWM signal on Pin 4 to control the fan speed but rather reduce the voltage on Pin 2 (like a standard 3-pin fan header). As the fan speed at minimum voltage is usually higher than the speed at 20% PWM duty cycle, the fan can not reach as low minimum speeds under voltage control as under PWM control. Please refer to your mainboard manual to check whether or not your mainboard has 4-pin fan headers that control the fan speed by reducing voltage on Pin 2 rather than by changing the PWM duty cycle on Pin 4:

4 pin fan header types

Note that mainboard manufacturers use different terms to indicate that Pin 4 is not being used for PWM control (e.g. “+5V”, “VCC” or “NC”), but if one of these terms is used, you can be sure that the fan header does not support PWM. If Pin 4 is described as “Speed Control” or “PWM” or the like, you can be sure that the fan header supports PWM.

Unfortunately, the description of Pin 2 is not always a clear indication as some manufacturers use terms such as “Fan PWR” or “Power” for both types of fan headers. However, if Pin 2 is described as “Speed Control”, you can also be sure that the fan header does not support PWM based speed control. If Pin 2 is described as “+12V”, this is a clear indication that the fan header supports PWM.

Please also note that in some cases, the descriptions of the pin layouts in the mainboard manuals may not be correct and some models actually allow you to switch the fan headers from voltage control mode to PWM control mode in the BIOS even though the pin descriptions do not indicate PWM support. We thus recommend to look for these options in the BIOS before taking other measures. In case of doubt, please contact your mainboard manufacturer.


If your mainboard features other 4-pin fan headers that use PWM for speed control, you can run multiple fans from these headers using Y-split cables. Make sure not to exceed the specified maximum power draw of the fan headers (usually 10-12W) though.

Can I use Noctua fans in my system from Acer, Apple, Dell, HP, Lenovo or other major brands?

Noctua 12V fans comply with the established specifications for standard PC systems issued by Intel and AMD. Systems from Acer, Apple, Dell, HP, Lenovo or other major brands often deviate from these specifications e.g. by using proprietary fan headers, custom pin-alignments or pin-configurations, different methods of fan speed control, etc. This can lead to compatibility issues when using Noctua fans in systems from said brands. Some of these problems can be avoided with some technical knowledge, but especially BIOS related issues (e.g. errors or shutdowns due to low fan speed) can often not be resolved. As a result, Noctua does not officially support systems from Acer, Apple, Dell, HP, Lenovo or other major brands.

Can Noctua fans be used to replace noisy stock fans in NAS devices?

Noctua fans such as the 40, 60, 80 or 92mm NF-A series models are ideal for replacing noisy stock fans in NAS devices in order to make them quieter and thousands of users have managed to significantly reduce the noise levels of their NAS units this way. However, while it is easy and straightforward to replace the fans in some cases, it can be very difficult in others, so Noctua strongly recommends that users carefully research if it is possible to easily replace the fan(s) of their NAS device before purchasing a Noctua fan for this purpose. Some of the common issues that can occur when replacing NAS fans are:

  • Different pin assignment: Whereas Noctua fans use the standardised pin assignment for PC fans (see this FAQ for details), some NAS units use different assignments. For example, some devices have the power and GND or rpm and PWM pins swapped. Therefore please carefully verify that your NAS device uses the same pin assignment as standard fans. Experienced users may also change the pin assignment by cutting and resoldering the fan cables, but please note that this will void your Noctua manufacturer’s warranty.
  • Different pin functions: Noctua fans use the standardised pin functions for PC fans (see this FAQ for details); however, some NAS units use fans where certain pins serve a different function. For example, some devices use the RPM pin for “power good” signals. Therefore please carefully verify that your NAS device uses the same pin functions.
  • Firmware speed control: Some NAS devices demand a certain maximum or minimum fan speed. If the new fan doesn’t have the same or similar maximum or minimum speed, the device may display errors or even shut down.
  • Different starting voltage: Most NAS devices use voltage-based speed control. If the new fan has a higher starting voltage than the original fan, it may not start up right away. This may lead the NAS device to display errors or even shut down because it suspects a fan failure.
  • Different power draw: Some NAS devices monitor the fan’s power draw. If the new fan has a lower power consumption than the stock fan, the device might display errors or even shut down.

Please note that most NAS manufacturers don’t provide detailed documentation regarding fan compatibility and control, so users who want to replace the fans of their devices usually have to rely on “How to” guides, blog and forum posts or video tutorials. For example, there are excellent video tutorials available for changing the fans in popular Synology NAS models (DS416j, DS1515+ and DS1812+ in English, DS416/DS415/DS916/DS216/DS214 and DS1515+ in German). Please also note that fan compatibility and control can vary from model to model and even from revision to revision even if the devices stem from the same manufacturer. As a result, it is important to make sure that the information or guidelines you rely on when replacing your NAS fan are applicable to your specific model as well as your specific hardware and firmware revision.

Due to the possible issues listed above, Noctua recommends that only experienced users attempt to replace their NAS fans. Please note that since there are so many different NAS models and most of them lack documentation for aspects such as fan compatibility and control, Noctua customer support cannot assist you with compatibility issues when replacing NAS fans. Please contact your NAS manufacturer for any questions regarding aspects such as the device’s pin alignment or fan monitoring and control.

Can I use Low-Noise Adaptors with y-cables / multiple fans?

Yes, Low-Noise Adaptors (L.N.A.s) can be used with y-cables, but please make sure to use one L.N.A. per fan and to place the L.N.A.s between the y-cable and the fans as shown below. Never use one L.N.A. for two (or more fans) by placing it between the mainboard and the y-cable!

D15S

I get a CPU fan error using my Noctua PWM fan, is it faulty?

Noctua PWM fans feature a minimum speed of 300rpm to allow for ultra quiet operation when your CPU is at idle state and doesn’t require higher cooling performance. Some mainboards display error messages such as “CPU fan error” during the booting process when the fan speed is below a certain level. If you get such error messages using your Noctua PWM fan and if such options are available in your BIOS, please either adjust the minimum fan speed monitoring limit to 200rpm or increase the minimum PWM duty cycle. If your BIOS doesn’t offer these options, please disable CPU fan errors. For detailed information on BIOS fan settings, please consult your mainoard’s manual or contact your mainboard manufacturer.

My Noctua PWM fan starts to spin when the PC boots but then stops, what is wrong?

Some mainboards feature 4-pin fan headers that actually don‘t use a PWM signal on Pin 4 to control the fan speed but rather reduce the voltage on Pin 2 (like a standard 3-pin fan header). In this case, it may occur that the mainboard reduces the voltage so much that the fan stops. Please refer to your mainboard manual to check whether or not your mainboard has 4-pin fan headers that control the fan speed by reducing voltage on Pin 2 rather than by changing the PWM duty cycle on Pin 4:

4 pin fan header types

Note that mainboard manufacturers use different terms to indicate that Pin 4 is not being used for PWM control (e.g. “+5V”, “VCC” or “NC”), but if one of these terms is used, you can be sure that the fan header does not support PWM. If Pin 4 is described as “Speed Control” or “PWM” or the like, you can be sure that the fan header supports PWM.

Unfortunately, the description of Pin 2 is not always a clear indication as some manufacturers use terms such as “Fan PWR” or “Power” for both types of fan headers. However, if Pin 2 is described as “Speed Control”, you can also be sure that the fan header does not support PWM based speed control. If Pin 2 is described as “+12V”, this is a clear indication that the fan header supports PWM.

Please also note that in some cases, the descriptions of the pin layouts in the mainboard manuals may not be correct and some models actually allow you to switch the fan headers from voltage control mode to PWM control mode in the BIOS even though the pin descriptions do not indicate PWM support. We thus recommend to look for these options in the BIOS before taking other measures. In case of doubt, please contact your mainboard manufacturer.



To resolve the issue, you can:

  1. Choose a higher fan speed profile in the BIOS (e.g. „normal“ instead of „silent“, etc.) or deactivate automatic fan speed control and use a Low-Noise Adaptor instead.

  2. Use the mainboard‘s fan speed control software or 3rd party tools like Speedfan to regulate the fan speed. Unlike BIOS based fan speed control, the supplied software usually checks whether the fan has stopped and increases voltage accordingly or at least offer more options to set up the fan properly.

  3. If your mainboard features other 4-pin fan headers that use PWM for speed control, you can run multiple fans from these headers using Y-split cables. Make sure not to exceed the specified maximum power draw of the fan headers (usually 10-12W) though.

My Noctua PWM fan runs at a much higher minimum speed than advertised, what is wrong?

The specified minimum speed refers to the speed at 20% PWM duty cycle. There can be several reasons why the fan doesn‘t go as low as indicated:

  1. Many mainboards do not go below 40%, 50% or even 60% PWM duty cycle on case fan headers. Please refer to your mainboard manual to verify whether the fan header actually goes down to 20% duty cycle. If that's not the case, in some cases you can use the fan speed control software supplied with your mainboard to overcome these limitations and reduce the fan speed even further. However, 3rd party tools like SpeedFan offer greater flexibility and better options to work around the limitations imposed by the mainboard vendors.

  2. Some mainboards feature 4-pin fan headers that actually don‘t use a PWM signal on Pin 4 to control the fan speed but rather reduce the voltage on Pin 2 (like a standard 3-pin fan header). As the fan speed at minimum voltage is usually higher than the speed at 20% PWM duty cycle, the fan can not reach as low minimum speeds under voltage control as under PWM control. Please refer to your mainboard manual to check whether or not your mainboard has 4-pin fan headers that control the fan speed by reducing voltage on Pin 2 rather than by changing the PWM duty cycle on Pin 4:

    4 pin fan header types

    Note that mainboard manufacturers use different terms to indicate that Pin 4 is not being used for PWM control (e.g. “+5V”, “VCC” or “NC”), but if one of these terms is used, you can be sure that the fan header does not support PWM. If Pin 4 is described as “Speed Control” or “PWM” or the like, you can be sure that the fan header supports PWM.

    Unfortunately, the description of Pin 2 is not always a clear indication as some manufacturers use terms such as “Fan PWR” or “Power” for both types of fan headers. However, if Pin 2 is described as “Speed Control”, you can also be sure that the fan header does not support PWM based speed control. If Pin 2 is described as “+12V”, this is a clear indication that the fan header supports PWM.

    Please also note that in some cases, the descriptions of the pin layouts in the mainboard manuals may not be correct and some models actually allow you to switch the fan headers from voltage control mode to PWM control mode in the BIOS even though the pin descriptions do not indicate PWM support. We thus recommend to look for these options in the BIOS before taking other measures. In case of doubt, please contact your mainboard manufacturer.


    If your mainboard features other 4-pin fan headers that use PWM for speed control, you can run multiple fans from these headers using Y-split cables. Make sure not to exceed the specified maximum power draw of the fan headers (usually 10-12W) though.

I'm experiencing fan speed issues with my motherboard from Supermicro, what can I do?

The BIOS of many motherboard models from Supermicro expects a certain minimum fan speed (usually 700rpm), which is higher than the minimum fan speed that can be achieved with Noctua's PWM fan models. The BIOS may interpret the low minimum RPM of Noctua fans as a fan error and thus try to run the fan at 100% for a short period before going back to automatic control.. This can result in oscillating fan speeds and fan speed warnings in the BIOS or the fan management console.

Unfortunately there is usually no option to set a lower minimum value that would suit the low minimum speed of Noctua PWM fans.The issue can thus only be resolved by either disabling automatic fan speed control in BIOS, which will cause the fans to run at a constant speed, or by requesting a modified BIOS file from Supermicro, which takes the minimum fan speed of Noctua fans into account (charges might apply).

Which Noctua fan or CPU cooler should I buy? How to choose the right model?

Not sure which Noctua product to buy? Our detailed buying guides for fans and CPU coolers help you to choose the model that works best for you.

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