Some models use an indicator light to signal use of the low-power mode.
Most screen-savers do not significantly reduce power consumption. For older monitors without an sleep mode, external control devices are available that shut the monitor off after a preset idle time. The monitor is then restarted when the keyboard or mouse is used. TCO is a labeling program for computers, monitors, and other office equipment that includes energy efficiency, environmental, and ergonomic criteria, as well as low electro-magnetic emissions. 486-7089 Lawrence Berkeley National Laboratory provided supporting analysis for this recommendation.