Abstract: Control of display power management by a host computer connected by a standard cable to a display monitor can be avoided by simply detecting user inactivity within a monitor or signaling such to the monitor with any one of the DPMS signals to the monitor, such as the video signal, i.e., the video intelligence signal occurring between horizontal synchronization pulses. In the absence of the video signal, the monitor commences timing of several display power management states without further reference to the DPMS signaling signals, except to monitor whether the video signal returns to normal. In the absence of a return to normal on the video signal, the display monitor transitions from a normal state to a standby state, thence to a suspend state, and finally to an off state. If user activity is again detected, a transition from any of these display power management states to normal is made.