so i have quake 4 and a brand new 15.4" MBP. its the 2.8ghz with the extra 512mb video card. i assumed that it would be able to play any game on the highest settings pretty much flawlessly, but for some reason quake 4 randomly gets laggy or jumpy. once or twice it just stopped, then continued after 10 seconds. is it just that intense or is there something i can do to make it run better? thanks for your time