Thanks for your response! I figured it out.
The board that I was considering (2nd attempt, ASRock H77 Pro4-M: http://www.newegg.com/Product/Product.aspx?Item=N82E16813157301)
would not have worked. I ended up calling EVGA about the video cards. So basically, the video cards need at least an x16 slot with PCI Express 2.0 x8 speed. So I needed to find a motherboard with 2 PCI Express 3.0/2.0 x16 slots that both can be at least x8 speed.
So your ASRock Z77 Extreme4 would work, but I already decided on MSI Z77MA-G45 (http://www.newegg.com/Product/Product.aspx?Item=N82E16813130647),
mainly because of lower cost.
Thanks again for your input! Much appreciated.