Hi guys new to this forum. I got my rock pi 5b up and running but the fan seems to be idle during boot and operations. I was wondering how to fix this? I used the default kit from Allnet China and I am very happy with them otherwise so this is probably something on my end. I connected it with the white plug and have tried both slots for this without success from either.
This is using the Ubuntu 20.04 server image.
https://wiki.radxa.com/Rock5/downloads
Someone did a great little program
But not sure what the ‘official’ line is.
But seems the pwm control is absent in later images /sys/devices/platform/fd8b0010.pwm/pwm/pwmchip1
As definitely was a /sys/devices/platform/fd8b0010.pwm/pwm/pwmchip1/pwm0/duty_cycle but doesn’t seem avail now?
Thanks I feel one step further. Still no spinning fan but now I got a program running in the background atleast 
I am not that sure as pumumu did a great little program but the duty cycle of the pwm confused me as seems unless above 55% the chosen driver doesn’t provide enough current.
It was there in earlier images but now seems to of gone might be an indication of probs and that maybe I shouldn’t of been using it on earlier images.
I overestimated how cool the Rock5b runs as thought the very hot Summer\Autumn had much to do with temps on the v1.3 pre-release board but prob passive aint enough with any continuous load and nvme onboard.
Its still an amazingly cool SoC for its power but keep thinking a side mounted fan blowing just a tiny amount both across a heat sink and a bit under the board would be more effective and keep the nvme a bit cool also.
So I don’t really like the heatsinks/fans on offer or my top down 12v 40mm on 5v but spotted some aliexpress stick ons that I can make sure the vanes are aligned for a 40mm side mounted fan 30mm above 10mm below that need to work out how to use the mounting posts to create a bracket
I got it working now by manually setting speed with fan control its spinning! wohoo
Also thanks for tips for further cooling !
Yeah I must of killed the install of https://github.com/pymumu/fan-control-rock5b as /sys/devices/platform/fd8b0010.pwm/pwm/pwmchip1/pwm0 disappeared until a fresh install.
If any of the 3d printer guys fancy creating a side mount for a 40mm fan that is approx 10mm below and 30mm above that attaches to the 2x mounting holes on the cpu side will get +20 from me
That is showing a 3pin fan but we are talking about the onboard 2pin fan header that is pwm controlled based on the measured temp by software.
After trying 20 cables I found one that worked and now 3/6 so far working. Let’s see if I can get the other 3 working as well. It did not output to HDMI when booting but I could reach it from SSH at least. After updating it booted from regular PD.
@eysteinh did you post on the wrong thread as struggling to understand that?
PS I really struggled to source fans with this connector so ended up getting these
Hehe yes posted in wrong thread.