That's an extremely old CPU and it probably will bottleneck your GPU.
I'm assuming you're saying you want to play all games on ultra settings @ 1920x1080.
That will be impossible with any of those two graphics cards, The 7750 and 7770 are only mid ranged budget cards which will only play games on low-medium settings if that.
My suggestion is you get a whole new computer, because even if you upgrade your GPU you still have an old CPU and motherboard which will bottleneck.
It can handle most games at 1080p.