I am trying to put together three 12 card rigs on these boards. I have one running stably with 8 cards. As soon as I add anymore cards I get issues. Upon boot SMOS recognizes all GPUS, they OC properly and display an appropriate hash rate. Immediately after, any cards over 8 crash to showing 0MH, weird values for clock temp and fan speed, and become unreachable by find GPU command. They are no longer in contact with the software. My HW is B250 Mining Expert, 3930 CPU, 4gb ram, OS on pen drive, two seasonic 1200W power supplies. I feel like I have eliminated risers, cards, ps, and slots. I believe the issue is software related.

Possible issues
The PS does not have enough connections to put 6 or 7 cards in group A. I can run 5 cards from each of the power supplies I have. I plan to change this in the future. Is it sensitive to not filling a group. For the next two rigs can I get three smaller power supplies and put four cards per group?
Low ram, the manual states assigning 30GB of virtual memory. Is this necessary or possible in SMOS. Would 8gb total ram be better?
Cpu?
Anyone have experience with this particular issue? I have more boards coming and can swap it out just in case that is the issue, but I want to get this solved before I order anymore components and I want to do that soon. Thanks for any help yall can provide.