Corrupted text at boot when graphics mode begin - how to fix?

[mrmazda]

@paju-21

server:~ # inxi -zaSMCG 
System:
  Kernel: 5.18.1-1-default arch: x86_64 bits: 64 compiler: gcc v: 12.1.0 
    parameters: BOOT_IMAGE=/boot/vmlinuz-5.18.1-1-default 
    root=UUID=d51abab2-5ba4-43da-9968-7ab5e8a641c6 **terminal=console nomode 
    set iommu=1 amd_iommu=on amdgpu.dc=0**

Have you tried booting with none of the highlighted options above?

nomode set

constitutes two non-options, while```
nomodeset

terminal=console

is not found on https://www.kernel.org/doc/Documentation/admin-guide/kernel-parameters.txt, so AFAICT, is another non-option.

Once you've completed booting and logging into Plasma, does Ctrl-Alt-F3 produce a screen containing any corruption? Does a subsequent Alt-F7 to return to Plasma produce any corruption?