I have this MB as well and had endless trouble trying to get more than 8 gpus running on it. My OS is Windows. I eventually stumbled across a YouTube video:
Asus B250 Mining Expert Bios Configuration
by Beardedbob
I changed the Bios settings on the MB and literally straight after that, I was able to set up and run 11 gpus hassle free
May be worth checking it out.
My virtual memory is set higher than yours though - pretty much set it as high as I could.
I wasted so much time assuming the issue was an OS issue. SMOS has a pretty good reputation so I would definitely check out the MB bios settings.