Question Bottleneck?

Does the 2600X perform as well as you'd like on minimal graphics settings? If no, then the 2600X is the bottleneck here. Are you going to crank all the visuals up and run everything at 4K? Then it might make sense to get one of those cards.

In any case, video cards don't limit what the CPU can do. Either the CPU can do it or it can't.