1080 resolution on a 1080p question

[NYbadboy911]

hi guys i just bought the samsung LN40B630 amazing tv but when i connected my tv to the computer i tried to set the resolution to 1600x1080 the picture is out of place but when i put it on 1050 its fine.
am i doing something wrong? or is there something wrong with my tv?

 

[Hefemeister]

Native res for that tv is 1920 x 1080. Set the resolution as such.