Ok I changed my mobo, made the necessary adjustements to Windows 7, and now Daz decided I am not interested in seeing a viewport at all. Everything else works fine. Opening existing scenes does not change anything. I've attached a screenshow - you can see what is available of the viewport in that tiny grey upper left corner.
Updated GPU drivers... no luck.
Reinstalled DAZ... no luck.
Tried the latest 4.9 public... won't even start.
This makes DAZ completely unusable of course.
Any idea?