FS Command Projector going off screen

I have a problem with a projector file set with the FS command to show full screen and to fit screen. Its on a widescreen monitor with the Flash canvas set to the correct dimensions for a wide screen. It was all working until I had to install a new graphic card and now it spills off the side of the screen although the Windows taskbar still fits fine. The screen resolution is set to 1024x768.

Has anyone heard of this problem before? As it was working before could it be a Flash problem or a hardware problem?

Thanks in adv.

Andy