Xbox 360 Dashboard Update aka the 1080p fix
 

The next time you sign into Xbox Live, you’ll be prompted for a dashboard update.


Improved support for HD video output over VGA, including 1080p resolution
Improved plug and play performance for wired headsets when being used with wireless controllers
Changes made to recently played games list to improve accuracy

http://www.majornelson.com/archive/2...1080p-fix.aspx