Comment # 1 on bug 105018 from Michel Dänzer

(In reply to L.S.S. from comment #0)
> I've thought about the possibility of it being DC-related as I saw similar
> bug reports, but I was wrong, as at one time I was able to reproduce it even
> after passing amdgpu.dc=0 during boot.

The rest of your report mostly points towards a DC specific issue. If you can
still reproduce an issue without DC, it would be best to file a separate report
about that.