Good cheap graphics card for fist upgrade?

Dunlop0078

Titan
Ambassador
Hello I have a dell dimension 530s desktop with a intel e4500 duel core duo 2.2ghz CPU, stock motherboard, Corsair CX500 PSU, 4gb DDR2 ram, integrated graphics at the moment which are useless, and stock 500gb hdd. I want to get a decent but cheap gpu that can play civ 4 and maybe 5, empire total war, and a few other strategy games. I would appreciate any help thanks.