A ton of people are having issues with the game. BF3 worked in window mode only for me and now that doesn't even work. I still lock-up and have to ctrl/alt/del to close it out. I've read that if you flash the gpu bios for that specific card, it's worked for some. The latest possible solution I've read is that the game is using alot of virtual memory, so adjusting it in windows to about 2.5-3gb have helped solve some of the crashing problems. This may help with you fps dips too. GL.