The pin configuration of Noctua 5V fans is identical to 12V fans:

While using PWM (Pulse Width Modulation) based fan speed control in PC environments is usually straightforward and does not require any background knowledge, it can be vital when it comes to controlling fans via PWM in other environments. Please refer to our specification white paper for a detailed technical documentation of the PWM speed control features of Noctua’s 4-pin PWM fans. Detailing aspects such as connector types, pin configuration or RPM speed signal output as well as signal specifications and circuit design questions, it enables engineers to implement PWM based speed control for Noctua fans in custom circuit designs and applications.

Please use 0.6Nm to tighten fan screws. Make sure not to overtighten the screws as this may damage the fan frame.

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.

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.

Noctua fans such as the 40, 60, 80, 92 or 120mm 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.

Noctua fans such as the 40, 60, 80 or 92mm NF-A series models are ideal for replacing noisy stock fans in switches, routers and other network devices in order to make them quieter and thousands of users have managed to significantly reduce the noise levels of their 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 network device before purchasing a Noctua fan for this purpose. Some of the common issues that can occur when replacing pre-installed fans are:

• Different pin assignment: Whereas Noctua fans use the standardised pin assignment for PC fans (see this FAQ for details), some network devices use different assignments. For example, some devices have the power and GND or rpm and PWM pins swapped. Therefore please carefully verify that your 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 network devices 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 device uses the same pin functions.
• Firmware speed control: Some network 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 network 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 device to display errors or even shut down because it suspects a fan failure.
• Different power draw: Some network 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 network device 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. 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 fans 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 pre-installed fans in network devices. Please note that since there are so many different devices 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 pre-installed fans. Please contact your network device manufacturer for any questions regarding aspects such as the device’s pin alignment or fan monitoring and control.

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:

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.

Both the NF-A4x20 5V PWM and NF-A4x10 5V PWM are great choices for upgrading the cooling of NVIDIA’s Jetson Nano Developer Kit. The NF-A4x20 5V PWM provides slightly better performance and is officially recommended by NVIDIA. Being slightly smaller (40x40x10mm instead of 40x40x20mm) the NF-A4x10 5V PWM is an excellent choice for more compact cases that can not fit 20mm thick fans. A 3D printed mesh case design that fits the NF-A4x20 can be found here.

Both models support PWM based speed control and can be connected directly to the 4-pin PWM fan header on the Jetson Nano Developer Kit, no adaptors are required. As the Jetson Nano provides 5V, please make sure to purchase the 5V PWM versions of the fans. The regular 12V PWM versions will not work. For a tutorial on how to set up PWM based fan control, please see this thread.

The mounting holes of the NF-A4x20 5V PWM and NF-A4x10 5V PWM align with the holes in the heatsink of the NVIDIA Jetson Nano Developer Kit. Please note that the holes of the heatsink are 2.5mm diameter and not threaded, so you can either use self-tapping M3 screws or regular M2 or M2.5 screws with nuts for mounting the fan to the heatsink. As it is not easy to hold the nuts in place, we recommend using self-tapping M3 screws, but please note that there can be aluminium shavings from tapping the thread, so make sure to clean off all shavings from the motherboard using canned air or a vacuum cleaner in order to avoid short-circuits. We recommend 15mm long screws for installing the NF-A4x10 and 25mm long screws for installing the NF-A4x20.

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.