is it worth going to the extra expense of jumping to a GTX770, or staying the the 670 / 760 price bracket. My requirements involve heavy open GL apps with a lot of textures (numerically, rather than size), so I am thinking the 760 offering 4G is going to be an edge on the performance of the 670. with the 770 another 100-200 bucks more, is it really worth it to go that route?