ON OR OFF?: Your computer is more likely to be damaged by a virus picked up from the Internet than by being turned off and on too much.
Image: Maciej Laska/iStockphoto
-
The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
Read More »
You take a deep breath, rub your tired eyes and prepare to push away from your personal computer after a lengthy instant message exchange, video viewing or analysis of your monthly budget—maybe all three. But before you exit cyberspace, a decision must be made: Should you shut the machine down, place it into "sleep" mode or do nothing at all?
How you end a computer session depends on how often you use the computer, your views on energy conservation (the amount of juice it uses while sitting idle), and what you have been told about how your decision will affect your investment's longevity: Will frequent starting and stopping cause its circuits to burn out sooner?
Rest easy, your computer is more likely to be damaged by a virus picked up from the Internet than by being turned off and on too much. They are also energy efficient: Such efficiency has reached the point where most PCs place themselves in sleep mode if they remain idle for a certain period of time. So your PC will likely slip into sleep mode anyway, even if you leave it on overnight.
Sleep mode itself, once a pretty unreliable option—you never knew if you would be able to wake your PC without having to reboot it—has been vastly improved with newer operating systems. If you want your PC to consume as little energy as possible when not in use, shut it down. If you want it to consume zero energy, you're going to have to unplug it.
Your PC can be in only three states: on, sleep or off (also called standby)—each of which draws some level of electric current. A PC that is "on" will either be actively processing information or sitting idle, depending on whether the user is typing a document, reading e-mail or has stepped away briefly. The amount of wattage drawn when the computer is on varies greatly depending on whether it is a laptop or a desktop PC. (The latter uses more energy because desktop power supplies are less efficient and require a separate and often larger, power-hungry monitor.) It also varies based on the type of work being done: Complex calculations requiring intensive processing are more power hungry, whereas writing or Web browsing consume far less electricity.
When a computer goes into sleep mode, it shuts down everything but its random access memory (RAM), a group of memory cells (which represent bits of data) that retains short-term data for easy access, thus preserving the computer's last active state—the running software, used log-ons and other settings—so that the user does not have to reboot when active use resumes. Sleep mode has gotten a bad rap in the past because, "with Windows operating systems prior to Vista [which debuted in late January 2007] the 'resume from sleep' mode has not been that reliable," says Ken Bosley, Hewlett-Packard brand manager for consumer desktop PCs. "Sometimes the resume fails and you have to reboot anyway."
"The usability benefits of leaving a desktop on appear to be growing as indicated in our focus groups," says Glenn Jystad, senior manager for desktop products at PC-maker Gateway, Inc., which in October 2007 was bought by Taiwan-based computer company Acer, Inc. "Nevertheless, it is prudent for home owners to manage their PCs power settings so as to not unnecessarily draw too much power and grow their electric bills." One trick Microsoft Windows Vista users can try is to select the "balanced" power setting, which causes the PC to go into sleep mode with one hour of nonuse, he adds.
See what we're tweeting about
9 Comments
Add CommentI have a six month old ASUS laptop that came preinstalled with Vista, it is pointless trying to use any form of sleep mode on it, since when it restarts, it will *always* crash, or at the least not reconnect to the wireless LAN. I also have a ubuntu desktop that runs 24x7, "sleep" modes are useless for both of these
Reply | Report Abuse | Link to thisYou fail to point out a key element of hibernating--when hibernating, a Windows computer uses ZERO energy; the power is off. This is especially handy for laptop users who have to watch battery life.
Reply | Report Abuse | Link to thisThe main consideration, as I see it, is heat. Computer chips including the cpu expand and contract with temperature changes. Thus if a computer is turned on and off frequently the chips which are pretty tiny are subjected to significant mechanical stress due to the expansion and contraction of dissimilar materials. The same applies to as simple a thing as a light bulb. The more you swich it on or off the more you stress it and the shorter its life. So the trade off may well be electric bill vs new computer bill. The cost of the electricity is far greater than the cost of the lightbulb.
Reply | Report Abuse | Link to thisThe title mentions the length of time the computer will last, yet goes into no details about that, rather it talks energy use.
Reply | Report Abuse | Link to thisGreat job.
I agree - there are two issues - one of component failure of the electronics due to being switched on / off and one of power conservation.
Reply | Report Abuse | Link to thisOn the power conservation, as long as the desktop has a transformer in it's power supply (as most do) or the laptop has charger attached, both will be drawing power unless the power is switched off at the wall socket or the cord removed, regardless of what the computer software is doing !
To respond to StandsWithADodecahedron comment. A computer always uses energy to keep the cmos battery charged. And most higher end motherboards have power LEDs on them to let the tech know the powersupply is still plugged in.
Reply | Report Abuse | Link to thisSome of us leave our computers on and blazing for SETI/Rosetta/etc... Maybe somethings are worth a few hundred watts.
Reply | Report Abuse | Link to thisIf I don't charge my laptop during the day but leave it charging overnight I save money on my electricity bill because of night-time electricity rates. But is this good or bad for the environment?
Reply | Report Abuse | Link to thisuseless
Reply | Report Abuse | Link to this