Okay, I'm not sure if anyone has had this problem yet, but my screen gets darker whenever I exit out of it using the tab. Example: I'm expecting an email from one of my closest friends, and I'm playing the Sims 3 while I'm waiting. I then use alt-tab(or open launcher in the options menu) to go back to the desktop and I see I get the email. When I go back to the game, it looks fine for a few seconds, but then the screen darkens and won't go back to normal until I exit out and start it up again. Any ideas on why it does this or how to fix it?