Before updating from the 61.77 drivers, I never had much of a problem. But since then I've tried the 66.70 drivers and now the 66.81 drivers and have had a minor problem since. It seems kind of random, but sometimes when I go to play a game everything is extremely slow and choppy. This happens in any game I play ie Doom 3, CS:Source. But if I exit out of the game, closing to the desktop then open the game up again... everything is back up to speed like it should be. Anyone have a clue what could be causing this?