Hi Daniel,  thanks for you help. Everything is set to the values you pointed out anyway. I verified that yesterday evenning, and saved values. However, tonight at 4 a.m., the notebook once again powered on.   Best regards Hartmut
The Inspiron 16 Plus boots from power off randomly at night - I went through all the power configuration to disable scheduled starts, wake on USB, WiFi, fastboot, hibernate is off etc.. All devices with power management (like USB mouse) are disabled to not wake the computer - powercfg shows no enabled devices and BIOS settings are also all set to not boot automatically. Still,  the computer boots itself without any interaction at night. I'm out of options what else could be done. Is there a log file what causes this? Some passive USB-C hub draws power even when the Inspiron 16 Plus is switched off. There is no BIOS option to disable the power-draw (yet?). Anybody with the same problem?
Inspiron 16 Plus (7610) switches on automatically at night - TB4 port always 
has power