I am a little confused. What does SLI have to do with a third monitor? You wanted to do Geforce surround vision? It kills performance from what I hear. Eyefinity is a much better option.
You could always just throw some cheapo card in for it though, and it will run at x4 on the 770 chipset. Or you could get a HD 5xxx and it can run three monitors by itself.
I think I will go with the 870, because it looks like it is more so for an overclocker newbie.
not sure I like the sounds of ''auto oc genie'' though. I thought I wanted to do that manually. I guess we will find out. Worst case senario I could return it for store credit and probably loose a few dollars and get the 770.
Although. What is your opinion on the Biostar TA790GX 3+?