Building Sub $400 PC (CPU)

Basically I just wanna know what CPU to go with.. I'm new to AMD and I wanted to try it out so I'm thinking between the 4100, 4170, 6300 whats the best price performence will I see a huge diffrence between the 4100 and 4170? 

or maybe even a phenom ii x4? 


a-10 for a 400 dollar system and than add another 7770 to get a crossfire effect later

No im pretty sure Im gonna go with Fx- 4170 and get a 7770 i already have some parts thats why i just asked for a cpu out of those  mentioned


get the phenom ii x4 965 its a little better then the first gen fx and then get a 7770 for the best budget performace