Things You'll Need
Instructions
Hook the Xbox 360's HDMI cable into the back of the console. The correct output is labeled "HDMI."
Hook the other end into an HDMI input on the TV.
Power on the Xbox without a game in the disc drive.
Change your TV's input to HDMI. Your Xbox 360's dashboard displays on the TV.
Go the the "System Settings" section of the dashboard, located in "My Xbox."
Select "Console Settings."
Go to "Display."
Go to "Screen Resolution."
Select the highest screen resolution possible for your TV from the list of settings. If you choose the wrong resolution, the screen turns black and the Xbox 360 reverts back to a resolution that worked.