Gnome Screensaver in Linux - Image Credit: lluisanunez on Flickr

It is a widely held belief that screen savers save on electricity when your computer is not being used. The truth is actually the complete opposite.

Screen savers are not power management features, which place the computer in a low power state after it has been idle for a specified amount of time (this is more commonly known as sleep mode).

What you may not realise is that screen savers can actually waste power as some prevent the computer from entering sleep or standby modes.

Some complex screen savers actually increase power consumption compared with normal use as the graphics card and processor have to work out more calculations to display the screensaver.

The original purpose of screen savers was to stop phosphor burn in. This is when text or an image has left a permanent ghost like image of what was on the screen such as a menu bar. 

This was a problem on CRT monitors and televisions and the best place to see it is an old ATM Cash Machine where please insert card is usually visible all the time.

Screensaver programs were designed to help avoid these effects by automatically changing the images on the screen during periods of user inactivity although the best way was to simply turn the screen off.

Modern monitors and LCD (liquid crystal display) televisions do not suffer from this problem and therefore screen savers are redundant with LCD monitors.

Yet they are still used, albeit for entertainment and security.

So when you next come to set your screen saver settings, instead of choosing a fancy screen saver, set your monitor to turn off after a period of inactivity.

This saves you money on your electricity bill and does not waste electricity which creates pollution when it is generated.