Hello every body which is the best and chep nvidia graphic card to be purchased which can play all games?

I have nvidia 512 MB 6200LE graphic card which is able to play the new games like devil may cry 4, tomb raider underworld..etc but not properly and in minimum graphics setting and it was not able to play the new call of duty 5 and also it will not play GTA 4 and all the coming games i think so. So please tell me the new series nvidia graphic card in range 2000 to 3000 Rs.