This should probably go into the support forum but I really wanted to get it out to the FFXIV crowd. Also I am not the most gifted writer in the world. I will do my best to make this as clear as possible. (Yes I fail at English) After talking with a few other players I think I have come up with a possible quick fix until S.E. optimizes the game. This is primarily for the GT 240 but could possibly apply to other cards with similar settings.
First go to the game config and set everything to standard with shadow detail set on lowest. Next turn multisampling to 2x MSAA. This has at least stopped the crashing in Black Shroud areas for a few of us that have the GT 240. You may see a slight visual glitching but its easier to live with then constant crashing.
Depending on the card you may need to lower settings below standard. For most people there is always that “one spot” where they can replicate the driver crash. For me it was that one city exit in Gridania. You want to log out near your crash point but not at it. Next go to your game config and set everything to lowest and set multisampling 2x MSAA. This will make the game look like an 8 bit pixilated mess but that is ok. You need to log in and see if you can stay on without crashing. If you crash with everything on low then its most definitely the card or your pc. If you are able to stay on without crashing log back out and bump all settings from 1 Lowest to 2. Repeat this process until you hit standard settings again. If you get to the point where you crash at say 6 or 7 but you can stay connected at 5 then you know that is the maximum setting your card will handle.
While the ultimate answer is S.E. optimizing there game I hope this band aid solution helps until then. If it does not work for you please be kind enough to post in the current support thread. I am not saying this will fix everyone’s issues but at least its helped a few of us stay on.