When you start to optimize a game, first determine where the application bottleneck is. Intel GPA can help you do this with some powerful analytic tools.If your game is CPU bound, then Intel VTune Amplifier is a helpful tool. If your game is GPU bound, then you can find more detail using Intel GPA.To fix GPU bottlenecks, you can try to find an efficient way of reducing draw calls, polygon count, and render state changes. You can also check the right size of terrain texture, animation objects, light maps, and the right order of z-buffer culling.
Assassin’s Creed* Rogue was optimized to run well on Intel® HD Graphics 4000 equipped PCs. This article describes what was done to enable the game to run at a solid 30 fps at 720p.