Hi all, hope someone can provide some clues as to what I need to do to get screen resolution from changing when I switch display settings from extended to duplicate screens.

PC is a self built machine with on Intel HD board graphics, however I am using a Radeon 6870 GFX card. the latest drivers have been installed (15.20.1062.1004-150803a-184226E)

I have a Dell P2414H monitor that is connected to the GFX card using DisplayPort cable and a 46" Sony HX823 LED TV connected via HDMI from the GFX card as well.

the monitor and TV both support 1920x1080 resolution and this is the resolution that the Dell runs on when the display setting is set to Extended Displays.

When I want to watch a movie I set the display to Duplicate Displays, the resolution drops to a lower setting as the taskbar and open windows all increase in size. the display properties however still report the resolution as 1920x1080.

Any ideas why this is happening? and what I can do to stop it from occurring?

Many thanks