Because a good 17'' or larger monitor can be used for several years on more than one computer, proper care is essential to extend its life to the fullest extent. Use the following guidelines for proper care of your monitors:

• Although phosphor burn (in which an image left onscreen eventually leaves a permanent shadow onscreen) is next-to-impossible with VGA-type displays—unlike the old TTL displays—screensavers are still useful for casual security. You can password-protect your system with both the standard Windows screensaver and third-party programs (although a determined snoop can easily thwart screensaver password protection).

Windows includes several screensavers that can be enabled via the Display Control Panel. A bevy of free and inexpensive screensavers is available for download from the Internet. Keep in mind, though, that add-on screensavers can cause crashes and lockups if they're poorly written or out-of-date. Use screensavers written for your particular operating system version to minimize problems.

• To prevent premature failure of the monitor's power supply, use the power-management feature of the Display Properties or Power (Management) sheet to put the monitor into a low-power standby mode after a reasonable period of inactivity (10–15 minutes) and to turn it off after about 60 minutes.

  Using the power management feature is far better than using the on/off switch when you are away from the computer for brief periods. Turn off the monitor only at the end of your computing "day."

  How can you tell whether the monitor is really off or in standby mode? Look at the power LCD on the front of the monitor. A monitor that's in standby mode usually has a blinking green or solid amber LCD in place of the solid green LCD displayed when it's running in normal mode.

  Because monitors in standby mode still consume some power, they should be shut off at the end of the computing day. If the monitor will not go into standby when the PC isn't sending signals to it, make sure the monitor is properly defined in Windows's Display Properties sheet.

  In addition, the Energy Star check box should be selected for any monitor that supports power management, unless the monitor should be left on at all times (such as when used in a retail kiosk or self-standing display).

• Make sure the monitor has adequate ventilation along the sides, rear, and top. Because monitors use passive cooling, a lack of adequate airflow caused by piling keyboards, folders, books, or other office debris on top of the monitor will cause it to overheat and considerably shorten its life.

If you're looking at a monitor with a partly melted grille on the top of the case, you're looking at a victim of poor cooling. If you need to use a monitor in an area with poor airflow, use an LCD panel instead of a CRT because LCDs run much cooler than CRTs.

• The monitor screen and case should be kept clean. Turn off the power, spray a cleaner such as Endust for Electronics onto a soft cloth (never directly onto the monitor!), and wipe the screen and the case gently.

• If your CRT monitor has a degaussing button or feature, use it periodically to remove stray magnetic signals. Keep in mind that CRTs have powerful magnets around the picture tube, so keep magnetic media away from them.