Upgrade my video card

My present video card is a Nvidia GeForce GTX 260. I really want to go up on my card, sticking with Nvidia chipset. My mother board is a Asus P5E3 Deluxe. Not sure how high I can go. The 260 wont accept Direct X11. Which rules out " Alien Isolation" and " Witcher The Wild Hunt ". Any help would be great.