[ The PC Guide | Systems and Components Reference Guide | Monitors | Monitor Power and Safety ]

Display Power Management System (DPMS)

Because of the tremendous amount of energy consumed by monitors when operating, a couple of initiatives have been started to work on reducing power consumption (and energy use) of monitors during idle periods. The US's Environmental Protection Agency (EPA) began a program called Energy Star to certify PCs and monitors that meet reduced energy use guidelines. These are sometimes called "Green PCs".

Most modern monitors are compliant with VESA's Display Power Management System protocol, also called DPMS. DPMS is used to selectively shut down parts of the monitor's circuitry after a period of inactivity. With a motherboard and monitor that support DPMS, power consumption can be greatly reduced. Motherboards that support DPMS often have a BIOS setting to enable it.

The operating system or application software you are using must normally also be set to activate DPMS after a defined idle period. Many monitors have two low-power settings; stand-by mode uses less power than the normal operational state, and then an even lower suspend or "shut down" mode turns the monitor off completely to save even more power. The system monitors the PC for activity and after the determined time, sends the appropriate signal to the monitor. When activity is detected again the monitor is "woken up" by the system.

One problem with DPMS is that if used improperly (such as telling the system to shut down after 1 minute of idle time) it can result in a lot of wear and tear on the monitor's internal components, reducing monitor life. Make sure to look at this section on maintenance for more on the pros and cons of power management. Even if you aren't using DPMS, at the very least no monitor should be left on for hours at a time if not in use, and especially not unattended overnight.

Note: Using a screen saver only, with no other power conservation features, has no significant impact on energy use of the monitor.

Next: Phosphor Burn-In and Screen Savers

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