So I installed Steam and Half Life 2 Demo on my 2011 15" MBP with 6750m. I tested it out, and I seem to get great FPS at any resolution settings. The problem is that when I "look" around the room or environment, I get this weird horizontal choppy effect where buildings and objects aren't lined up perfectly right. Basically it's as if the image is getting cut, and the bottom or top half is lagging behind by a few frames. Is anyone else having this prob? Could it be an OpenGL and/or 6750m issue?