Additional Thoughts on Savers and THeir Uses

Monitors that are running free screensavers consume the same amount of power as when running normally, which can be anywhere from a few watts for small LCD monitors to several hundred for large plasma displays. Most modern computers can be set to switch the monitor into a lower power mode. A power saving mode for monitors is usually part of the power management options supported in most modern operating systems, though it must also be supported by the computer hardware and monitor itself.

Additionally, using screensavers free with a flat panel or LCD screen instead of powering down the screen can actually reduce the lifetime of the display, since the fluorescent backlight remains lit and ages faster than it would if the screen was turned off completely. As fluorescent tubes age they grow progressively dimmer. A typical LCD screen loses about 50% of its brightness during a normal product lifetime. (In most cases, the tube is an integral part of the LCD and the entire assembly needs to be changed out)

Thus the term "screen saver" is somewhat a misnomer—the best way to save the screen (and also save electricity) would simply be to have the computer turn off the monitor.

Notice also that screensavers as well as free screensavers may utilize a significant amount of CPU time. On a busy server this might be a problem.

Screensaver programs were designed to help avoid effects by automatically changing the images on the screen during periods of user inactivity.

Older machines designed without burn-in problems taken into consideration often display evidence of screen damage, with images or text such as "Please insert your card" (in the case of ATMs) visible even when the display changes while the machine is in use. Blanking the screen is out of the question as the machine would appear to be out of service. In these applications, burn-in is prevented by shifting the position of the display contents every few seconds, or by having a number of different images that are changed regularly.

Modern CRTs are much less susceptible to burn-in than older models due to improvements in phosphor coatings, and because modern computer images are generally lower contrast than the stark green- or white-on-black text and graphics of earlier machines. LCD computer monitors, including the display panels used in laptop computers, are not susceptible to burn-in because the image is not directly produced by phosphors. For these reasons, screensavers today are primarily decorative or for entertainment, and usually feature moving images or patterns and sometimes sound effects.

One increasingly popular application is for screensavers free to activate a useful background task, such as a virus scan or a distributed computing application. This is convenient because these things only use resources when the computer would be otherwise idle, and thus are very efficient.