Im running one hx1000 and one rx850w for a 6 vega rig no problem. There is enough pci-e connectors, some cards will need to use the daisy chain 2x6+2pin pci-e cables for power. Im sure the hx1000w has 5 pci-e terminals and comes with 2x 8pin-6+2pin and 2x 8pin-2x6+2pin cables