The 7950 should beat the 580 if overclocked. (With a little less power usage.)
The fx 8320 will have an edge over the q9550 in Games that rely on mult-threading, but overall not worth the money imo.
Better save some more and go for an Ivy/Sandy-Bridge+mobo.
Or use the 7950 with Mantle. 
"Enlightenment is man's emergence from his self-imposed nonage. Nonage is the inability to use one's own understanding without another's guidance. This nonage is self-imposed if its cause lies not in lack of understanding but in indecision and lack of courage to use one's own mind without another's guidance. Dare to know! (Sapere aude.) "Have the courage to use your own understanding," is therefore the motto of the enlightenment."
