Samsung PN51E6500EFXZA - Manual (Page 618)

Try resetting the picture to view the
default picture settings (go to Picture
→
Reset Picture ).
There is a dotted line on the edge of the
screen.
If the Picture Size is set to Screen Fit ,
change it to 16:9 .
Change the cable/satellite box
resolution.
The picture is black and white.
If you are using an AV composite input,