You cant take advantage of crossfire in FFXIV windowed mode. Rendering the game unplayable for anyone relying on a 2nd card. The game doesn't even want to run crossfire in full-screen unless you tweak things with radeonpro. Not to mention there's no proper full-screen windowed mode so you have irritating borders, and god forbid you can't play at your native resolution so the game is stuck in a little cub on the desktop. :/
If anyone wants to fork out 400$ for a new videocard I'll gladly take you up on the offer because it's going to take 6 months to build my new pc otherwise lol. :P

If the game was proper DX10/11 xfire would work windowed, but we don't have that luxury. Though enabling 10/11 would negate the positive effects of crossfire in the first place.

I'd be willing to put money on it that SE doesn't see this as an issue. FFXI was "designed" the same way. They wanted to give the "Console experience" (barf) to PC users playing the game. Guess they didn't think that I play on PC because I don't like the console experience. Anyway, I don't think it would be an easy fix. It would probably take an extensive rework of something.

Still wish it would get done.