Press the Xbox button to open the guide, and then select Profile & system > Settings > General > TV & display options. Select Refresh rate > 120 Hz. Note If you don't see an option for 120 Hz, select 4K TV details under Setup for more information.

The 120fps mode works beautifully on PS5 and Series X, while Series S is no slouch either - though 60fps offers more consistent performance on the slimmer console.