If your cpu is giving you a bottleneck then you would have to upgrade your cpu and motherboard. So far with the specs u enlisted, those hardwares should be running good. If you do upgrade your cpu+mobo then ofcourse you would have to reinstall windows and give u a fresh start.
you can either a) over clock that cpu or b) buy a new CPU
the company i got it from overclocked it already and im not sure i trust myself enough to fiddle with it.