1. A device for parallel multithreaded blending in graphics systems comprising of: means to receive a plurality of color components and alpha information from source and destination image fragment streams; a blender processing unit capable of combing in parallel the color and alpha channels from pixel fragments in the source and destination images in order to produce a pixel fragment value of a target image, the said blender processing unit capable of executing up to at least two parallel threads of operation; a storage device that holds a sequence of operations for the blender processing unit; synchronization and alignment circuits between source and destination fragment streams.