I do not fully understand the PCI-E 16x, 8x, 4x situation with sli. I wanted to do 2 970's in sli and a 750 ti as a dedicated physx. (Not looking for feedback on using dedicated physx, it works for me.) I havent dont sli before and wondered if there would be this 4x power issue i see people talk about if i did this setup. I have the Asus Z-87 Pro motherboard. EVGA Supernova 1000 Watt 80 plus Platinum PSU. And a 4770k. Thanks for helping clear this all up.