Need help or suggestion

I'm building a desktop for my brother and his gonna be playing games like left 4 dead 2, cs:s, starcraft 2, football manager. So which CPU and GPU combination should i go for? Any suggestion and is being used on a 17 inch monitor. Thanks in advance

hd 5770 + athalon II x2 or x3 + 4gb ram, nice asus board to match, rosewill challenger case, 32gb HDD.. make good

So a dual-core would be sustainable right? and how much watt do i need for this set-up 500Watts?