Between the above cards, is there much diffference? I plan to drive a seiki 4k 39 inch tv so I think VRAM Matters. Also are there any cards that have the green "NVIDIA GTX" or GEFORCE GTX" logos on the side? I really want my build to look nice. Any suggestions?
Nope, don't really want to game with this system. It was more intended for photoshop, premiere pro, and after effects work. If I want to game I'll use my backup 1080p monitor . I went with NVIDIA because of CUDA, and how much it will help. Currently, even the 760 4GB is pushing it, but if I need, I repeat absolutely NEED to upgrade I will try.
Have you checked to see if your software favors Cuda VS. AMD's architecture? Some software heavily favors AMD over Nvidia. However, for general purposes I say the 760 4GB is fine. Heavy rendering may be a bit much though.
a gtx 690 would definitely get you through it is two gtx 680 in one card but is not sli so it would be great for rendering, but i would recommend getting the 4gb eddition and it will work just fine in a single pci express 3.0