Go step by step: 1. maybe you are trying to set a higher resolution then the screen can be 2. its possible that your comp don?t recognize the screen right, check the "display properties" make sure it?s the right model 3. reinstall the drivers. Restart. 4. if its not the software it?s the hardware, try connecting the screen to another computer if it works fine the problem is in the display board . Good luck
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