We're excited to announce that we've fully migrated the Xbox Forums to their new home, here on the Microsoft Community forums!
As of today, going to forums.xbox.com will redirect you here to the Xbox area of the Community forums. We've moved all of your existing threads over so you can continue and start conversations with the new forums experience.
We sincerely appreciate the feedback you have provided over this transition and can't wait for you to check out the new Xbox Forums!
In short, you'll need to connect the Xbox 360 with an HDMI cable. If the Xbox 360 is an older model than the current Xbox 360 E, you can alternatively get a component cable (red, green, blue connectors) or a VGA cable, depending on what inputs your TV offers.
When connected by an HD capable connection, the output resolution can be selected in the display settings on the Xbox 360.