How can I upgrade my PC? (not sure if this is the right subreddit)

Ok so I build my PC last Christmas and it was a beast I've been able to play all my games on MAX-Settings but now and then a game comes along that I can't play on the highest settings so here is my setup any suggestions on how to upgrade? -16GB Ram -Intel(R) Core(TM) i7-2600 CPU@3.40GHz -EVGA GTX 560 Ti -Intel DZ68DB

Hope somebody can help or suggest me a better subreddit for questions like this! :)