hi guys! im having a hard time choosing which gpu to buy for my upgrade. im replacing my good old sapphire 6870 hd. im planning on playing batman origins and battlefield 4. with nvidia i can have this physx for batman and if i go for amd i have this battlefield 4. my choices would be gtx 770 4gb. gtx 780, r9 290x and 7970 ghz. im leaning towards 770 but i have a good experience with amd. if any of u guys can enlighten me on which gpu is better, im open for suggestions. thanks in advance.