I upgraded the BIOS of my S1200V3RPM (XEON E3 1265L V3) to 3.03.0006
To do this, I insterted a USB stick with the new BIOS, booted to the internal EFI shell and then the BIOS upgrade started by itself. It ran through to the end without any issues.
I then power cycled the machine to reboot and now it does not boot anymore. No beep, so POST screen, nothing.
How can I get back to a working machine?