How can I tell if a new graphics card will suffice?

Hey all.

It's probably been asked before but please bare with me since I could not find a relevant solution.

My CPU is i7 @3.50, I have 32GB Ram and Win10.

My Graphic card is an Nvidia Geforce GTX660.

When editing 2K and above my system stutters and that's a pain.

Will a new better card do the trick or is only a more comprehensive upgrade do the work?

I do not want to upgrade my entire pc obviously but do wish to work properly...

I'd really appreciate your experienced feedback.

Thanks