Samsung SyncMaster 400DXn Owner's Manual page 67

You cannot preview the office files for the source and background.
Background
This is for configuring the background for all screens. The background consists of the Area,
Screen, Music, and Effect functions. If a color or photo is used as the background, you can
freely place other areas such as a movie and text on the background to compose a varied
screen. If an office file or an external input is used as the background, you cannot place other
areas on the background and will need to compose screens with the background only. The Area
function allows you to set the size of the background and the total period of time that all
screens are played. The Screen function allows you to set the background content you want to
use. The Music function allows you to set the background music. The Effect function allows you
to set the effect used when the background changes.
Area
Name: Changes the background name.
You cannot use a name already used for another area name.