[Build Help] Looking to upgrade

Hey guys,

Built my own pc a year and a half ago and I'm looking to do my first upgrades. I play a lot of online games and stream occasionally. Lots of web browsing and some photo editing. I notice currently drops in FPS when playing and utilizing more of my computer. I also use 3 screens. Thanks again for any suggestions, comments, or help.

Here is my part list:

Intel Core i7-3770K 3.5GHz Quad-Core Processor
CPU Cooler Thermalright Silver Arrow CPU Cooler
Asus P8Z77-V PRO ATX LGA1155 Motherboard
G.Skill Ripjaws Series 16GB (4 x 4GB) DDR3-1600 Memory
Samsung Spinpoint F3 1TB 3.5" 7200RPM Internal Hard Drive
Crucial M4 128GB 2.5" Solid State Disk
Galaxy GeForce GTX 680 2GB Video Card
Corsair 600T (Black) ATX Mid Tower Case
NZXT 750W ATX12V / EPS12V Power Supply
LG GH24NS70 OEM DVD/CD Writer
Microsoft Windows 7 Home Premium SP1 (64-bit)
Das Keyboard DASK3PROMS1SI Wired Standard Keyboard
Logitech G500 Wired Laser Mouse