Connecting power supply to Zotac GeForce Gtx 980 Ti etc

All right so I'm hoping someone could educate me lol. I just built my first computer and have a question with hooking up power supply to graphics card. I have a EVGA 220-G2-0850-XR 80 PLUS GOLD 850 W ECO Mode Fully Modular NVIDIA SLI Ready and Crossfire Support Continuous Power Supply and the graphics card is a ZOTAC GeForce GTX 980 Ti AMP! Extreme, it has two eight pin headers. All right so power supply comes with plenty of connections. I plugged the eight sided pin header into the motherboard and then the other end going into the graphics card has 1x6 pin header and 1x6+2. I plugged the two 6 pin headers into graphics card one in each eight pin header. The problem is the 2 pin header goes no where so I have a video card with a 6 pin header plugged into each eight pin header on board. Which leaves two pins on each header for the card empty. Now I kinda of feel like both eight pin headers on the graphics card should be completely filled. Not sure if that is correct or not.

Your psu comes with 4 x 6 + 2 Pin PCI-E, 2 x 6 Pin PCI-E, so why dont you use both 6+2 pci-e connectors?

@04dcarraher: the plus two does not match up to the graphics card. That is why I only have a 6 pin going into each of the two eight pin headers on the graphics card. I have 12 pins being used out of 16, so does it matter if the other 4 are used or not? Then if I do want to use them is there something I can go and buy.

6+2 snap together they will fit

You should have several of these cables (see pic). Just hook/snap the 2pin next to the 6pin and plug it in.