I also have a GTX 970 and have been crashing in DX11. I was excited to try it out in DX11 as soon as early access was available, but within several hours of playing, my screen went totally black but the sound continued - nothing could recover my display, no matter what I tried - I couldn't alt/tab to another window, I couldn't ctrl/alt/del to bring up the task manager to close FFXIV, nothing was responsive. Ultimately I had to do a hard shutdown to fix it. After that I tried launching in DX11 again, but this time after a shorter window of time, the program errored out and closed on its own (at least it didn't lock my whole system this time).

I was running it on the most current drivers at the time - so I think that was 353.06 (a new driver has since come out which I just applied this morning but have not tried playing with yet - 353.30). I’m on Windows 8.1.

Dropping the client back down to DX9 has resulted in a stable experience again, so I'm pretty sure it's not my hardware (i.e., I'm pretty sure it's a driver issue).

Would sure be nice if there was a fix for this though :-( I want to enjoy the graphics at the highest level that my machine is capable of presenting - having just built my machine a few months ago, it should be no problem for the hardware to handle the requirements, but when the drivers won't play nice, well...