I've got a used APU2C board from family and would like to fresh install a new OS.
When I connect via the serial console, I do see the board booting and can interact (change boot device, perform memory test,...) for a few seconds (around 10-50s) before the console freezes.
It then doesn't show any new output and doesn't respond to any input.
Reconnecting doesn't work, I have to reboot the board.
I've tested with Linux, MacOS and Windows with the clients Minicom, Screen, Putty.
I've tested 2 different USB console adapters and different RJ45 to RS232 adapters. All show the same behaviour (except that it doesn't work at all when using the wrong pin-out).
Connection settings are 115200,8N1 as suggested in various docs.
Could anyone point me into something I've missed or things I haven't tried yet?
Any help is greatly appreciated.