You could probably do with giving more details about the screen you are looking at and what the rest of your system is so people can help you better. For example, no amount of GPU upgrade may be of use if your current CPU is too underpowered to take drive it. Likewise if you get a 34 inch screen (ultrawide is it?) your current system may struggle to actually push out the pixels fast enough to make it fun.
Let us know what you have and what you intend to do with it!