I have been googling problem obvisouly ... I am found a couple of places where people have the same problems and could not fix them and this Moherboard is basically Crap ... Can someone confirm this so I can return this product ASAP
Don't blame the board. I am running two of those ASROCK boards, each with four Sapphire R9 270x GPU's without issue. The 270's have dual PCI-E power connectors on the back however.
I agree with the powered risers. Sounds like a power issue to me.
Added: None of my cards are in the slots, all but the 4th card (in each rig) using powered risers.