well is it a monitor or tv? try a different scaling mode. i suppose there are two options aspect ratio and full screen mode.also do you know the panels native hz?is it 60 or 75?sometimes some panels work on 59hz. also there are known issues on windows 8(if you are using). untimately if you want only picture i would suggest a dvi-d if possible.
Its probably just temporary but it makes me wonder if my other display is only 1050p. I am using a 55" Samsung smart TV. So no dvi
I tried different scaling methods. Neither worked. Since its a 3D TV, I'm gonna assume that its native rate it 120Hz but it goes to 59 hz by default for some reason. And last but not least I'm using windows 7 home premium.