Crashs during booting - what's happening here

Hey guys,

my system has the following problem during booting. Arrow+Enter-keys are not movable any more. Nor does it perform a memory test correctly or lets me enter the system password in order to enter the bios setup.

What's wrong here?

Linux Mint 19.3 still runs fine on the same machine.

I load up 5 photos showing the states of system-freeze-crash I speak of.

Can anyone tell me what these problems mean or even better how to fix them?

Matthias
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