BeagleBone AI - Severe thermal issues

[Michael Zoran]

 I just got my BeagleBone AI today from mouser, and I'm noticing severe thermal issues even when the BeagleBone isn't doing much.

/sys/class/thermal is reporting over 100C within 10 minutes of the power being connected.

At which point the safety features kick in and the power to the device gets shut off.

Is this normal???  Does the BeagleBone AI require a fan to be usable at all?

Also of interest is the free command is showing only 512MB of RAM instead of the 1GB it should.

And the /proc file system is showing that a very generic device tree is being used.

This is an AI directly out of the box using only the preinstalled software.   I'm waiting for the serial debug cable to arrive that I ordered today

before I try reinstalling everything and maybe try lowering the clock speed.

Just thought this would be useful to other people.

[Dennis Lee Bieber]

On Mon, 23 Sep 2019 16:40:23 -0700 (PDT), in
gmane.comp.hardware.beagleboard.user Michael Zoran

<mzoran-O+n0w2l...@public.gmane.org> wrote:


> I just got my BeagleBone AI today from mouser, and I'm noticing severe
>thermal issues even when the BeagleBone isn't doing much.
>/sys/class/thermal is reporting over 100C within 10 minutes of the power
>being connected.
>At which point the safety features kick in and the power to the device gets
>shut off.
>

debian@beaglebone:~$ uptime
00:42:24 up 19 min, 2 users, load average: 0.21, 0.17, 0.17
debian@beaglebone:~$ cat /sys/class/thermal/thermal_zone*/temp
74100
72600
73000
73000
74100
debian@beaglebone:~$


Not as bad as yours, but still rather hot -- enough that I can only
rest a finger on the heat sink for a few seconds. And I though my R-Pi 3B
running at 50degC was high. I ordered through Newark -- if that has any
relevance.

>Is this normal??? Does the BeagleBone AI require a fan to be usable at all?
>
>Also of interest is the free command is showing only 512MB of RAM instead
>of the 1GB it should.

Interesting -- mine shows

debian@beaglebone:~$ free -h
total used free shared buff/cache
available
Mem: 610M 194M 97M 26M 318M 377M

which is NOT some common power-of-two, and is also much less than I'd have
expected even if the graphics system is using part of it (300MB for
graphics buffering?)

--
Dennis L Bieber

[aras...@gmail.com]

There are so many more cores in the AM5729 SoC than there are in a RaspberryPi SoC. The reason heat is so high on the BeagleBone-AI is due to all these cores enabled at once. If you are not using the board connected to a display then you should disable the HDMI peripheral, GPU core, and IVAHD core through the device tree. This can be done by setting status = "disabled" for the modules mentioned. This alone will drop your temperatures to 55C. I also modified CPUfreq to run at 1GHz minimum instead of 400MHz minimum and I am still seeing 55C idle.

Regards,

Ahmad