I know most people like to have two cards of the same model for sli, but they can be different ones as long as they're 970s. So you could get a shorter 2nd card and sli in your case, if you wanted.
I've had mine for over a month and still haven't played any games on it... FML![]()
Didn't realize that about SLI, then again I see no real reason right now to even bother. The 970 alone is pretty much capable of handling anything I throw at it anyway. Kind of waiting for the next 'tentpole' PC release that will justify this card also as most of the intensive PC releases I already either own on PS4 or just aren't very interesting despite the taxing visuals(Ryse, DR3, AC Unity).
It is nice being able to see a lot of my 360 library(and games I missed) running at 1080p60, but even they are starting to look a bit dated(FC3, Dishonored, Borderlands 2, Saints Row 3/4) though I am gearing up to give some Skyrim mods a shot soon. Oh and PhysX in Borderlands 2 is pretty damn impressive, my first taste of the tech.