What you can do about hardware to increase performance, you obviously going to buy new computer parts suitable on your motherboard. (duh)
What you can do about software to increase performance, try
Razer Game Booster.
It basically shuts down services and programs (at your choice) to increase some available RAM space, and when you exit your game, it restores all previously terminated services and most of the programs.
It also features a free Windows Tweak function, basically tweaks windows to increase performance, A free driver update tool (consider updating drivers, it also increases performance), a game derfag tool, which defrags game paths to make your game load faster, and lastly a FPS tool which is "onboard" of the program, it will help you monitor the performance of your PC.
Some other features lies beyond.