Well voirin, thanks, and you are correct. You know I am about 75% comfortable using Device Manager, but how you managed to correlate controllers to plugs is beyond me. In any case, this is the reply I received from ASRock (thanks Eric Lin):
Intel USB 3.0 is the one in the middle
Asmedia USB 3.0 are the one on top.
ASRock America Support Team
So there we have it. For reference if anyone else needs to know.