Lee, the motherboard in my sig has 8x PCI-e on the 3rd slot. I bought it to run a 3rd 570 with. I'm not sure if it's Ivy Bridge compatible, though. I saw one newegg reviewer say it was but haven't confirmed anything yet.
I bought mine open box so got it a little cheaper than that. Comes in today, so I'll be testing it soon. HardOCP gave it a good review.
Edit: This one may suit your color scheme better, the Maximus, and it has 8x PCI-e on the 3rd slot as well: