I don't know why, either. Sometimes, it's an easy fix - Intel's integrated GPU doesn't always know when a game needs to run off the nVidia GPU on my laptop, so I have to switch them manually. But even doing that for this game made basically no difference. I have no idea why, it's like some Unity games (and recently a CopperCube 6 game!) just hate my PC. I can run UE4 games at max settings at 60 FPS, so it's not like my card's a total slouch for a laptop. I don't get it.