Werner

Best chance to get an idea about the temperature is a laser thermometer I guess...

For other distributions you can always install mesa from source. Also there is a PPA from oibaf which though does not seem to cut it with its the prebuild debs. Had more success with doing the first variant.

armbianmonitor -u

I think these wishes, besides the DE are out of range for Armbian. Armbian provides a usable kernel for many different boards and puts a OS over it with minimal adjustments to provide a mostly untouched experience with that OS. It is up to you to customize your OS as it is in any other distribution. By the way you can customize it even at image level while building. Check https://docs.armbian.com/Developer-Guide_User-Configurations/#user-provided-image-customization-script

Simply build a kernel package and then extract the created source debian package and check that particular file

Feel free to drop an image for the OPi1+ somewhere and I'll test it. I'm just out of time until monday.

1810000 -> 1488000 Did you reload cpufrequtils afterwards?

How?

Also my guess since [ OK is missing before the ] ...

You are way outdated. This old release is not supported anymore. How do you power the board?

Welp, nothing much that can be done about unfortunately...

If anyhow possible always provide the output of armbianmonitor -u along with bug reports.

Of course. The fat "Documentation" button on top between Download and Subscriptions https://docs.armbian.com/ To get some things sorted out beforehand: Check which kernel sources the tinkerboard uses (hangle yourself from the board config to the source config). Then you will also know the patch folder where kernel patches are held and applied to the sources before building.

Maybe PAE is missing in the kernel?

The description is probably outdated.