Good morning and thank you for posting on the Final Fantasy XIV Technical Support Forums.

Do you recall if this was a custom resolution you made? If so, it would be deleted when you reformatted your PC.

If you are able to select 3200x1800 at 60hz, you should be able to limit the frame rate to 30hz in the Display Settings in game.

We hope we can be of assistance in helping you enjoy the exciting world of Final Fantasy XIV!