If you are into software, and if you need to demand more you have to prove you can write very complex code so that company never dares to replace you. So you can demand increments whenever you please since your code is not possible to easily modified by others.
If your code is easy to modify...
ok, go for Asus N7600GS , will cost abt 12.5K and its just right for your budget. But I don't know about other games but I ran NFS PRO Street on my card. But I don't think you can run Assasins Creed on that card. But I'm not sure abt that.