I'm a bit of a nooby and I need some help giving power to my new EVGA GeForce GTX 1060 SSC. Here are my specs for my mobo, gpu and PSU:
Motherboard: Asus z170-p
Graphics card: EVGA GeForce GTX 1060 SSC
Power Supply Unit: SeaSonic S12II 520 Bronze 520W
So my issues is this, on the GPU I have an 8pin PCI-Express port and on my PSU I also have 8 pins. I was only provided an 8pn to 2 6pins PCI-Express with the 1060 (refer to bottom picture as reference).

I tried connecting the PSU to gpu using an 8 pin to 6+2pin PCIE however, it doesn't seem to have enough power.
Any suggestions? I would appreciate all the help!