Screen tearing with two monitors

Hi

I purchased myself a second screen this week so I could have a set up where I could run Prepar3D on my main screen and have Plan G or FSC on the second screen for navigation. What I have noticed is that while running the two monitors I get a slight tearing on the main screen while panning around, inside or out but this does not happen if I only use the main monitor (second one switched off ). My first screen is a Dell E248FWP set at a resolution of 1920x1200 and my second screen is HKC with a maximum resolution of 1920x1080. Is the difference in the resolutions the problem, I can set my Dell to 1920x1080 but it narrows the screen a bit which I don't like. I have tried different settings using Nvidia inspector but to no avail. Is this a problem I can cure. Thanks for reading.

Cheers Shaun