GPU not showing up?

Alright so I'm running
an asus maximus viii extreme
i7 6700k
32gb of ddr4 ram
yada yada, all that works fine because my pc is running off of on board video.
But it isnt detecting my asus gtx 1080 strix oc at all
The 8 and 6 pin power are plugged in and there are 2 white lights right next to them. but none of the other lights are coming on.
The 8 and 6 pin are both the same cord though, so I'm running it through 1 single VGA cord. it has an 8+6 at the end.
Any suggestions on what I can do to make it work?

Solved!
I didn't have any of the PCI lanes turned on. Simple fix once I actually got a big picture look at everything lol

Thanks for the follow up
Love those easy fixes

First question was going to be if you could see it in the BIOS... glad you got it!

Yeah! I'm glad it was something easy and quick.
Can't believe it took me so long to realize it though.