Connect the Xbox Series X to a 120Hz-compatible TV or monitor using a high-speed HDMI 2.1 cable
Turn on the TV or monitor and set the HDMI input to the correct port
Open Xbox Settings
Go to General
Select TV & display options
Select Video fidelity & overscan if needed and confirm the display is recognized correctly
Select Refresh rate
Choose 120Hz
Set Resolution to 1080p, 1440p, or 4K based on your display’s 120Hz support
Go to Video modes
Enable Allow 120Hz
Enable Allow variable refresh rate if supported
Enable Allow auto low-latency mode if supported
Enable Allow HDR10 or Dolby Vision if supported by your display and desired
Open your TV or monitor settings
Enable Game Mode or low-latency mode
Enable HDMI Enhanced, Input Signal Plus, or the equivalent 120Hz/HDMI 2.1 setting for that port
Restart the console if the 120Hz option does not appear
Launch a game that supports 120fps and enable its 120Hz or performance mode in the game settings
Verify the game’s video output or performance settings are set to 120fps
Check the Xbox TV & display options screen to confirm the signal is running at 120Hz