So quick question. I'm building my first PC and have quick question regarding GPU installation. Have everything except for the GPU which will be an EVGA 1080 FTW2. Also have the Corsair RM750x. I'm also using the custom cable set from Corsair and was wondering do I need 2 separate 8 pin PCIe cables or the one that's single 8 pin on the PSU side and dual 8 pin on the other end? Thanks for any help you can give.