I would suggest you make a new post, for this upgrade, in the SYSTEMS category. You can link to this thread or just mention what you have and where you'd like to go with however big your budget is.
I would say and fx-83xx series or any of the last few generations of i5 or i7 would not bottleneck a gtx960.
You also have another issue if you consider upgrading. The MS 7778 is usually an OEM board (Hp,Compaq in this case) which means you have an OEM version of windows which cannot be moved to another motherbd without MS's ok. The restore disk set usually check the motherbd model# and wont install unless it detects a compatible one.