Depending on the game, your performance could be limited by a CPU that old, but I'd recommend one of the AMD Radeon HD 7700 series cards. If I were in your position, I'd probably grab a 7770. What games are you planning on playing? Some of the modern games are going to perform poorly on a low clocked older dual-core CPU like that.
first, thanks for the quick answer. I want to play games like Dota2 and League of Legends at MAX settings without getting fps lag and i want to avoid bottleneck :P
My monitor max resolution is 1280x1024.