i have like 6 peices of the 270 A and AR asus and they work with up to 8 gpu rx 570 or 580 easy
are you sure you dont have a bad board? they really have problems with 6 plus vega?
I hope not becuase i like these boards since they have their own power switch too and have been for the most part solid. I only have 3 vega so i cant test it myself
did u update bios to latest?
I have the 270-As and they run 8 580s fine. I have 2 rigs like that but none of my VEGA rigs can handle more than 6 which bums me out since I love those mobos as well