I can’t provide much info up front as I would have to pipe it to a file, swap hardware, and reboot every time (or transcribe by hand) but i will do so for anything you guys need on request.
My PC currently has a Ryzen 5 2400G in it. When graphics output is through my motherboard, everything works buttery smooth and lovely. As soon as I move the hdmi cable to the GPU and reboot, though, it gets to the end of boot just fine, then never starts my display manager. Just sits at the end of boot. Quick tapping the power button powers off cleanly just fine as I’d expect from a working machine, I can get myself into a tty just fine with ctrl-alt-f2. The only problematic thing I see in the boot printout is at the very beginning: I get an “unable to write to IOMMU perf counter” and then a bunch of APCI ERRORs: Aborting method due to previous error. It’s highly possible I’m just doing something stupid here- this is my first time trying to use a dedicated GPU, and I don’t really know what I’m doing.