While you gave him the right links I am only chiming in to mention this is a point of contention with me too.
AMD has made it so you have to have a pro card to use their cards on a server. Nvidia and Intel do not do this. Mind you AMD did not do this till a couple years ago.
Most servers are not work stations an do not benefit from a pro card and further makes it very hard to recommend using AMD on a Sever. As APUs are soon coming with 8 core or more configurations. These would be very good entry level servers that can't be do to AMDs choice to not allow the compatible server drivers to load.
So to the OP, I feel your pain and don't get it either.