Comment # 35 on bug 1193250 from Michal Suchanek

(In reply to Felix Miata from comment #33)
> To multi-user.target, it boots so fast that nothing shows up on either
> screen until a whole screen full lights up with a login prompt at the
> bottom. I can see near black change to black about halfway through the few
> seconds between Grub menu and login prompt. When I boot directly to
> graphical.target, nothing shows up until the TDM greeter.
> # cat /proc/cmdline
> ...mitigations=auto video=1440x900@60 vga=791 3

simpledrm should still show up in the kernel messages if it's working