12 months of trying to resolve SLI - time to turn to square enix

[CHA0S_DECEPTI0N]

Try this.

Open Catalyst control Center Latest Version.
Go under "Gaming" and open up "3D Application Settings" and click Add.
Search and find "ffxiv.exe" in your benchmark/game folder and select it (You will have to do this to the main exe during launch as well)
Scroll down and under "AMD CrossfireX" change the "AMD CrossfireX Mode" to "Use AMD pre-defined profile"
Search for "fear.exe" ***(You don't have to own the game to select this option, it's there by default.

Whoops Sorry for the wrong post, I was tired.

OT: Try changing your game profile at Driver Level. That could work in your case. But Yes as others have said it is SE Fault and they really should optimise this game for modern systems. Not everyone uses a Dinosaur Rig.