Its was a finger-feeling and not a external temperature meter, but I think I found "my problem".
First after yor message I did use the internal temperature meter named
cat /sys/devices/virtual/thermal/thermal_zone0/temp
cat /sys/devices/virtual/thermal/thermal_zone1/temp (not available at Mainline Kernel)
So I did try Stock-, Legacy- and Mainline-Kernel:
Stock Kernel
Linux OrangePI 3.4.39 #2 SMP PREEMPT Mon Nov 21 16:23:11 CST 2016 armv7l GNU/Linux
idle 66-67 degree Celsius
SanDisk Ultra SDHC 16GB Class 10
Legacy Kernel
Linux orangepizero 3.4.113-sun8i #18 SMP PREEMPT Thu Jun 15 02:16:06 CEST 2017 armv7l armv7l armv7l GNU/Linux
idle 62-67 degree Celsius
Kingston SDHC 8GB Class 4
Mainline Kernel
Linux orangepizero 4.11.12-sun8i #1 SMP Wed Aug 23 15:21:32 CEST 2017 armv7l armv7l armv7l GNU/Linux
idle 54-58 degree Celsius
SanDisk Ultra SDHC 16GB Class 10
As I didnt got a third "SanDisk Ultra SDHC 16GB Class 10" I used a "Kingston SDHC 8GB Class 4" for the Legacy-Kernel.
Above we can see that there isnt much difference between Stock and Legacy-Kernel here (in the end 67 degree idle), BUT
I must admit that the OPi Zero is getting hotter around the Class 4 Kingston Card against the Class 10 SanDisk Ultra.
So my finger-feeling could belong to a hotter MicroSD-Cards rather than to the complete system which is measured from the internal temperature-sensor.
I have to check if the Legacy-Kernel would be running cooler if I flash it on the Class 10 Sandisk Ultra.
Do you got informations about different temperatures with different MicroSD Cards?
I did got this as a problem on my mind.
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Iam very pleased with the work from the armbian-teams - also for the OPi Zero.
I understand to esteem the hard work here while not getting informations from the maker-companys of the boards.
For me you are all very cool doing support for single-board-computers which have lost their manufacturer-support sometimes after an initial release.
I know the v1.4 doenst seems the best revision of the board in meaning of heat - but I does come with the kit to me
If there is the legacy working for me (with a newer MicroSD Card) then there is no problem for me to wait for a great mainline-kernel.
And if there will be audio included I will be very happy.
The "few amateurs" be certain to do a great job!
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