PLX chips act like a dual gate so you can have your 16 channels on the CPU side of the chip and 32 channels on the other side for the PCIE graphics cards. The only problem is there is a bit of a delay with this. It is only really needed to go with three or four graphics cards on 1150 socket processors or four on the 2011 socket processors. For one or two graphics cards, even on a 1150 type processor, you don't need them.