With one of those in-house mining enthusiasts leading the design, we developed the original B250 Mining Expert with support for up to 19 individual GPUs. The board was so ahead of its time that miners couldnt fully exploit it at first. We had to work with AMD to remove restrictions on the number of Radeons capable of running in parallel before miners were able to realize the boards potential.
This will probably hold for the new MB too. Bleeding edge motherboard...