I have a force3d 4870. It has two pci-e power slots. My psu only has a single pci-e connector. I have a 2x 4 molex to 6 pin pci-e cable, can I use this for the second pci-e slot? If so how would I connect the molex ports? Do I connect both on the same cable from psu or separate? Or do i only connect one.