Good evening everyone. I have had my rMBP for around 3 weeks now and it has been running great until this morning. I was playing Diablo 3 and it runs great even at max settings. All of a sudden it started to have horrible lag. I have restarted and even left it off for a few hours but now even typing this it is having trouble keeping up. As I type there is a second or so lag before it appears on the screen. The only thing that seems to be acting normal is mouse movement. What could have happened to cause this lag and what can I do to fix it?