The usual thing to try is turn on Vsync in the game or card which you did. However duplicating the display is probably a problem since the displays are rarely identical. In other words, don't duplicate.
Bob
I recently bought a Samsung smart TV, to connect to my pc for gaming on a bigger screen. But there is slight screen tearing when moving the camera. I've found it doesn't happen if I set the Tv to the main display or if I disconnect the PC monitor. I've adjusted the resolution for both and enabled vsync but still getting the tear if I do the duplicate display method. Any clue to a fix where I could either do the duplicate display or leave my pc monitor as the main display?
TV model : Samsung UN55H6300
PC Specs
WIndows 7 64-bit
16GB Ram
Processor: AMD Phenom II X6 1100T
Video Card: AMD Radeon HD 6800 Series

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