3D doesn't seem to care what card you use after a point. I had a 670 (only a tad slower than a 770) and it worked great for 3D, but you'll find alot of games have issues and simply have bad CPU/GPU utilization and so bad framerates, even if they work just fine in 2D. Moved to a 780 and it made zero difference in 3D.
Honestly I wouldn't recommend buying into 3D anymore, its pretty much a dead technology. It's fantastic when it works, but for it to work you have to rely on community fixes, something that aren't being made anymore due to the incapability to fix DX11 games. Made worse is the fact that Nvidia (in response to the majority of modern games not working with 3D) is now putting out drivers that use fake depth buffer 3D, so all...