I don't think it's productive to think of things in terms of bottlenecks. You need a certain amount of CPU power to get 60fps (or whatever fps you're aiming for) in a game - it doesn't matter what GPU you have. A more powerful GPU will let you run higher graphical settings, but ultimately your CPU is what determines how smooth your game can play, and your GPU, how pretty it is.
A 1050 Ti will work with a G2030, but many of the more demanding games will always have low framerates due to lack of CPU power, even if you lower graphical settings.