I hope nothing I say breaks the NDA, but here goes anyways:
I can safely say that you wont need a GTX 4xx to play FFXIV. The beta version of the game will run at mostly max FPS (it's capped at 30) with all graphical settings set to max, except for anti-aliasing which was set at 2x instead of 8x, with the following specs:
Intel Core2 Duo E8400 3.0 Ghz x2
nVidia GeForce 8800 GT 512 MB x2 SLI (though I think SLI is still not enabled in the beta, but I may be wrong).
4 GB RAM
Windows Vista 32bit
Having said that, the resolution was only 1680x1050; however that's still pretty nice considering the two year old graphics card and CPU.
As far as I could tell, the frame rate did not drop noticeably when in large crowds, but did dip slightly when it rained. In instanced zones it was always at the cap.
Edited, Jul 11th 2010 3:59am by Mase