I have the Winner ZIV (Zorro IV is an invention of Elbox)
Basic Zorro slots are Zorro-II, not III. It is alround known as the most compatible busboard of them all.
This weekend i'm going to try my other A1200 mainboard. I don't trust the one which came with the tower, it already gave me the impression it's not stable, even without the busboard/mediator I often got crashes and hangups. The other a1200 was solid as a rock.