Lol I tested Z270-A PRO MSI and i had up and running 6 gpus. Now i can run only 5 I messed with options. Anybody have this motherboard and can tell what did you changed to work 6 gpus ?
Enable 4G Decoding & set PCIe to x1
Did it help? I have 4 pieces in the basket in the eshop and I hesitate to order it.