A 6870 is going to struggle at EyeFinity resolutions. Even with a 7870, you will still NOT come close to maxing most games. With that being said, out of your two options I'd go option 1 simply because the 7870 with the extra ram will make a large difference at the resolutions you are going to be playing at. As far as the sapphire flex, rather than that just get any 7870 and a $20 adapter and you'll be fine. While a monitor with displayport natively would be preferable, its not a requirement, especially since the adapters are much better than when EyeFinity was released and much cheaper. For a displayport cable just check monoprice, they're cheap. Also, if you want to consider a monitor besides the dell look at the Asus VE248Q, I run 3 of them for my EyeFinity setup, HDMI and Displayport.