I had the same issue.  I think it is because Asus uses a CPU based onboard graphics card.  SMOS and Claymore try to use that as a gpu for mining and it slows everything down. I couldn't get it to work with SMOS and 12 cards.

Tytanick,

I have been trying to get the new Asus expert mining board to work for a couple of days now.  The problem seems to be the onboard graphics are run by the CPU and SMOS thinks its a GPU for mining.  When claymore boots up it uses the onboard graphics, which gets 4mhs, but it slows everything else way down. The keyboard response time goes to 5 seconds between when I press a key and when it shows the character.  This seems like a maxed out CPU to me.  I tried running 12 msi rx 580 8gb cards running on it and they get 4 or 5 mhs as well.  I have 4 other rigs with 12 RX580's and they get 29.7 mhs each running fine on the biostar BTC pro board.  I would love to have 19 cards running on one rig but until Asus updates their board or you implement a fix for their poor graphics design, I don't think these expert mining boards will work well.

Another issue with the Asus board is it takes more than 100 times as long to load the DAG file to each card, the overclocking part also takes 10 times as long.   Both of these could be related to the CPU trying to act like a GPU.  

Perhaps I'm wrong and some one else has been able to get this board to work in SMOS with 12 or more cards.  I searched the thread and found nothing.