Abstract: A peripheral device having a circuit to detect the power management state of a central processor, a first interface to receive data, and a second interface to couple the peripheral device to the central processor. The peripheral device prevents data transfers that would cause the central processor to change from a second power management state to a first power management state if the central processor is in the second power management state.

Abstract: A method for displaying graphics in a computer system is described. In one embodiment, the method includes a step of receiving a stream of data into the main memory of the computer system. This stream of data comprises a series of descriptions of digital video frames and a series of indicators, each of which corresponds to a set, or a group of one or more, of the video frame descriptions. Each indicator indicates a basis for selecting a subset of the set of video frame descriptions. For example, in one embodiment thirty video frame descriptions are in each set, and a given indicator indicates that half of those thirty descriptions should be included in the corresponding subset. Then, only the fifteen video frame descriptions selected for inclusion in the subset are decompressed, and only the fifteen resulting video frames are displayed, while the other fifteen frames are dropped.