Z270-A can have 9 GPUs.
I have Z270 Prime P and It can have 8.
i am currently running 8GPUs on my z270-A but from what i hear, if i want a 9th card it will have to be a completely different maker for windows 10 pro to pick it up.
( EX: 8 = GTX1060s and 1 = rx580 )
can anyone confirm this?