suitable gpu for my system

[Dimitar1988]

Hello guys. I want to buy new GPU for my old computer. My cpu is AMD Athlon X2 7750 Black Edition and my current gpu is Sapphire HD 4830. Im between HD 7750, HD 7770 and HD 7790. What would you suggest? Which one is more suitable for me? Will be the HD 7790 just a waste of money because of my old cpu?
I really appreciate any help you can provide.

 

[woltej1]

the 7790 will be a waste, go with the 7770.