GTX Titan is really fast but too costly. HD 7970 GHZ is fast, but some comparison videos I watched shows smoother gameplay experience, no shuttering or lag in GTX 680 as well as GTX 680 provides better color saturation, if I look at water or human faces its better in GTX 680 than in 7970. Also whether you have enabled PHYSX, or any other Nvidia specific things? because that will reduce the fps too. Because the difference seems unbelievable. Generally GTX 680 provides much more crisp and clear images than 7970?why?