I have an iMac, Mac Pro, & Mac Air. They basically all have 2GB of Memory. They are all in the 2GHz area. I don't understand though, why does My Mac Air get very slow, and overheat when playing a game. Same with my Mac Pro, it overheats and also goes very slow. iMac has like the same GHZ and memory as my laptops, so how come it doesn't ever get slow when playing the same game, like my laptops do?