Just SLI the GTX 670 you already have. The only real difference in the GTX 770 and the GTX 670 is boost 2.0 and higher VRam clock. The GTX 670 and GTX 770 are based off of the same exact silicon. It is in no way shape or form new silicon period. You already have a good GPU and it would cost less to just SLI what you have instead of scrapping a really good GPU.
As others have said we really do not know what the next gen games will require and there fore no one can say for sure if a GTX 770 will even play them for sure. At this point it may take a GTX 8xx card to play correctly and then you have spent money on a GTX 770 for nothing. Best bet wait and see how the games perform and the based you buying needs at that time. It may very well...
Depends on the resolution you want to play at. @1080p I'd say it probably would but can't really give a solid answer till the games release and/or get benchmarked.
As long as the CPU isn't a bottleneck then you maybe able to run and max setting but as mentioned its all a guessing game till the games benchmarks come out.
Probably not going to bottleneck then. Even of you can't max you will probably be able to get decently high settings barring any sloppy programming like a bad console port.
Just SLI the GTX 670 you already have. The only real difference in the GTX 770 and the GTX 670 is boost 2.0 and higher VRam clock. The GTX 670 and GTX 770 are based off of the same exact silicon. It is in no way shape or form new silicon period. You already have a good GPU and it would cost less to just SLI what you have instead of scrapping a really good GPU.
As others have said we really do not know what the next gen games will require and there fore no one can say for sure if a GTX 770 will even play them for sure. At this point it may take a GTX 8xx card to play correctly and then you have spent money on a GTX 770 for nothing. Best bet wait and see how the games perform and the based you buying needs at that time. It may very well be that at 1080p the card you have now will work great only time will tell.