Any source saying that GA10x lacks HDMI 2.1? I find that hard to believe.
GA100 is a datacentre part that doesn't need to have display controllers, so they are probably just saving space.
The second chip on other side still sounds implausible. BUT if we assume for a moment that its true IMHO it could be a DL inference chip. I am just speculating here.
Some people on this thread have suggested that its a RT accelerator chip or another GPU, but a DL inference chip makes more...