The CPU and RAM is OK. I'd look at SSD to give an all around boost.
500GB SSD run about 120 here and will give you an overall boost.
Go compare your 770 with today's 970 and 980 at GPUBOSS.com
I built my computer about 3 years ago and i'm looking to upgrade some of the parts to keep it up to speed with the fast developing game industry so it can run these new games with no problem. In the past i've had no problems running the best of the best (GTA 5, Skyrim, etc.) but recently as new games come out i'm beginning to run into some lagging and screen tearing. (GTA 5 gave me some issues as well)
GPU: GeForce GTX 770
CPU Intel Core i5 3570K @ 3.40 GHz
Memory: 8gb Ram (i should probably upgrade this?)
Powered by: Corsair CX600
i can't think if i'm missing any of the specs... if you have a question let me know... but i want to know which i should upgrade and hwat i should upgrade to because i want to be able to play more games at higher graphics and speeds.