Samsung PN51E6500EFXZA - Manual (Page 236)

feature.
●
Side Gray
Lets you select the color of the
sidebars your TV displays when you set
the screen size to 4:3.
Auto Protection Time
for LED TV
If the screen displays a still image for
a certain period of time you define, the
TV activates the screen saver to prevent
the formation of burnt in ghost images
on the screen.