[Zomboy]

For that kinfd of price I would suggest you to go with AMD Radeon r9 270x(it can go bit above you're budget but its worth it) as thats the best in the range you're looking for. You can play high end games like BF4, GTA V on medium settings without any lag or fps drops.
However, if you're not an AMD fan you can go for Nvidia GTX 750 Ti which is much cheaper but wont be as gaming friendly. But you wont have any complaints either.