I have had a problem displaying a full picture on my friends Philips 42" ambilight...
When I sent the signal to my friends 42" Philips TV it runs off the edges of the screen. When I start moving the resolution to lower resolutions it just gets smaller on the screen... till... I get to 1360 x 768 then it jumps back to filling the whole screen. I can get my 1920x1080 signal to display but i have to use the Intel graphics accelerator medis driver program to scale down the size by 35% horizontaly and 50% verticaly...
To me this would say that the TV does not actually display a 1080p signal... but maybe has a go at processing it the incoming signal.
Unless its the signal my laptop is putting out... but then if a computer cant display a resolution, it wont!
Personnaly I think that since the day wide screen first came out... we have always had settings on our TV's which dont fit right on the screen and either we put up with having black lines on the edges, missing parts of the picture or having the picture squashed!
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1360 x 768 is likely the native resolution of that TV.