Idle unexpected shutdowns

Hi there, I’m new here with a vim3 pro. Yesterday night I went to sleep with my vim in idle (I have an m2x extension with an nvme ssd, and also official heatsink+fan) and now in the morning I noticed it crashed, all LEDs went off, the board hotspot (sta+ap) wasn’t connecting anymore (but I could find it on my phone!) and touching the board it was really hot. During the night I woke up to the fan spinning but I also have to say I made some modifications the day before to my Ubuntu installation (kernel 4.9 and on EMMC):

  • set CPU governor to ondemand at boot
  • changed the activation temperature for the fan (with a custom dtb) to 58 degrees and to 68 for the mid speed with removed high speed as I am a student and I am going to live with other people who would probably be annoyed by a high speed small fan (I prefer having my CPU throttling)
  • setup STA+AP in 5GHz.

Clicking the board buttons didn’t reboot the board for me while it was hot in that dead mode with no LEDs on, only removing and reinserting the USB c cable worked. My power supply is a 5v 20w and I directly power the board from the board’s USB-C port. Maybe some components on the Vim overheated and when the fan switched on it was too late? Do you have any idea on what I can do to test it out? Thank you very much