Akuman1 :
Did you say you used to get 40 to 50 fps? Do you get more now?
Yes. Around 40-50fps with drops to 30, according to stage and number of enemies, with my fx-6300@4.2ghz and evga ssc 960 2gb.
Finished the game, don't play anymore.
If you oc your gpu maybe you'll get better min fps.