When a complete power shutdown occurs, the backup battery kicks on within milliseconds, an alarm goes off and the computer user is given valuable minutes in which to move to the keyboard and shut down applications. Higher-priced UPS home office models have computer connections and come with software that can automatically shut down systems if no one is there to tend them. UPS boxes were once essential, high-priced pieces of only the largest corporations. They re well worth the price, Staples says. Prolonged electrical outages are not the primary culprit chewing life from computer components.
Brownouts can happen so quickly that the human eye can t detect that the lights have flickered.
When a computer suffers that kind of outage, a lockup or freeze can result. The screen may appear unchanged. Sometimes, the cursor can be moved around, but the computer won t respond otherwise. Brownouts rob computer memory modules of their ability to keep track of what s happening on the desktop. A power interruption of only a 50 billionth of a second can cause RAM chips to suffer amnesia.