(In reply to Harry Wentland from comment #17)
> I don't have that laptop but this link mentions a method to "Update the BIOS
> when Windows does not start": https://support.hp.com/ca-en/document/c00042629
> 
> I'd be more curious to know if the patch I posted fixes it.

I tried the linux-amd-staging-drm-next kernel (which should already have the
patch if the other comments are to be trusted). I have the same error as
comment #19, but the screen goes completely blank while the system stays
responsive. I can even start X and run glxgears in it, although the screen
still stays black and I can't see anything. It runs at 60 FPS for the first ~5
seconds, then drops to a steady 1 FPS.