Abstract: A method and apparatus for displaying graphics data and video data, such as a video window, on a computer display. A graphics adapter chip stores graphics pixel data in a graphics memory, and a video source stores video pixel data in a video memory. The graphics and video memories sequentially output blocks of pixel data to the display screen on output channels. Graphics data is selectively outputted on a number of graphics channels and video data is selectively outputted on the same number of video channels. The video channels are multiplexed with the graphics channels to form the output channels and either graphics data or video data can be output to the display on each output channel. A number of dummy video pixel values can be inserted before video data in the video memory to align video pixels between blocks of graphics data on the display screen.