bad experience with ASUS Maximus V Extreme mb

[netMonet]

ASUS Maximus V motherboard has PCIE slots spaced in such a way that GPU cards can be pluggen in with a one slot space between them to provide a breathing space for card fan. But this is miselading! The black slot is DISABLED when more than two cards are used. There is no warning on the box or in the promo materials. This information is hidden deep in the manual.
Tried ribbon cable to use 3 GPUs and have adequate spacing. This motherboard is unreliable with 3 GPUs, worked fine with 2 GPUs.
Had to return the mb as faulty to the store.