nVidia-spec'd Noctua 40x20mm PWM fan fails to start spinning

nano powered by: 20W 5V barrel
brand new fan

commands used:
sudo /usr/bin/jetson_clocks
sudo sh -c ‘echo 255 > /sys/devices/pwm-fan/target_pwm’

Fan is brand-new out of the box. It spins fine at all frequencies,including slowest speed, when connected to a separate desktop PWM fan controller.

However, when using above-mentioned commands to turn fan on at full speed (255 out of 255), it will only stutter and fails to start spinning. IF pushed along with a toothpick, it starts up and spins fine.

I have tried “breaking it in” by running it on nano at full speed, as well as on the desktop computer’s PWM fan controller, for about 24 hours total, but the undesired failure to spin-up still remains.

Any suggestions, other than running the 40x10mm fan instead?
(i suspect that for some reason, my particular nano board lacks the “juice” to spin-up this 20mm thick fan, despite the fact that other folks are pleased with the fan on their nanos…)

The one you linked to is the 12V version. You need the 5V version as defined on the wiki https://elinux.org/Jetson_Nano#Other . Please check the vendor’s page https://noctua.at/en/nf-a4x20-5v-pwm

Thank you.


Is there a way to increase the voltage for the 12v fan to work well?
I have to spin it manually from time to time, but generally it works.
Probably I will not be procuring another fan, unless I got another jetson, but if the voltage could be adjusted that would work for 12v fan autostart, wouldn’t it?

You may try a DC/DC step up module, such as this cheap one.

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Thank you for pointing out!