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Five PC Power Myths Debunked

snydeq writes "Turning off PCs during periods of inactivity can save companies between $25 and $75 per PC per year, according to Energy Star, savings that can add up quickly for large organizations. Yet most organizations remain behind the times on PC power management, in large part due to common misperceptions about PC power, writes InfoWorld's Ted Samson, who outlines five PC power myths debunked in a recent report from Forrester, ranging from the energy savings of screen savers, to the energy draw of powering up, to the difficulties of issuing patches to systems in lower-power states."

29 of 551 comments (clear)

  1. a PC actually wrote this article by cornercuttin · · Score: 5, Funny

    this article was written by a self-aware PC who is tired of the human race's waste of time and energy.

    1. Re:a PC actually wrote this article by Mononoke · · Score: 5, Funny

      this article was written by a self-aware PC who is tired of the human race's waste of time and energy.

      Would it still be self-aware if we turned it off?

      I'm sorry Dave. You can't do that.

      --
      NetInfo connection failed for server 127.0.0.1/local
    2. Re:a PC actually wrote this article by plague3106 · · Score: 5, Insightful

      See, your math is nonsense. Not that it's wrong, its just that you CAN'T combine all those minutes to get something productive. The minute I save each day isn't going to make a difference to the next day.

    3. Re:a PC actually wrote this article by online-shopper · · Score: 5, Insightful

      That's why you use WoL to boot the system one hour before employees arrive, do a virus scan, check for updates, or other maintenance tasks.
      1 hour is generally enough time for updates and virus scan. Employees come into a machine ready to go, you get regular maintenance and everybody's happy.

    4. Re:a PC actually wrote this article by gfxguy · · Score: 5, Funny

      You must have missed the posts from a few days ago...

      It's been determined that step 4 is "ask for a government handout/bailout."

      --
      Stupid sexy Flanders.
    5. Re:a PC actually wrote this article by mcgrew · · Score: 5, Insightful

      That step is only applicable if you are super rich. These days only billionaires get welfare.

  2. The units! by Thelasko · · Score: 5, Insightful
    They're all wrong! Ahh!!

    The average desktop draws 89 watts per hour. If it's left on overnight for 16 hours, it consumes 1.42kW. It's impossible for the power surge that occurs when powering on a PC to rival that figure: "You would be drawing energy at a rate of 17 kWh"

    Energy is kWh power is kW. "Energy at a rate" is power, and should be in kW not kWh.

    --
    One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
    1. Re:The units! by madbavarian · · Score: 5, Informative

      Same here. This is the point I stopped reading too. Anybody that thinks that a PC takes 89 watts per hour isn't worth listening to for technical advice. The next line just cemented it for me "If it's left on overnight for 16 hours, it consumes 1.42kW." Aaarrrrg. How did our basic science education go so wrong??? Please tell me that this guy is really a movie reviewer that is sitting in for the technical person as they take the holidays off.

    2. Re:The units! by Yvan256 · · Score: 5, Funny

      What do you mean, an european or an african kW?

    3. Re:The units! by sjames · · Score: 5, Funny

      So does that mean on my last trip I drove 720 MPH?

    4. Re:The units! by evanbd · · Score: 5, Interesting

      If you need a convenient size, that's what the prefixes are for. A MJ is as conveniently sized as a kWhr. Whr is more convenient in some applications for calculating energy used over time, so it's a reasonable thing to use there.

      Miles per gallon is a silly set of units to use. Metric units would be nice, but have little practical benefit for most usage cases (unless we were to switch to selling liters of gas and marking roads in km, but that's unlikely). The problem is that miles per gallon is backward. It should be gallons per mile (or 100 miles something similar for convenient scale). Why? Distance is the independent variable, not the dependent one. You might want to know how many gallons you'll use on a 200 mile trip, but it's unlikely you want to know how far a trip you can go on with the 8 gallons left in your tank. Furthermore, it's not convenient for comparing operating costs either. You drive your car a certain number of miles per month, not a certain number of gallons. If I want to compare three cars that get 20, 30, and 40 mpg, the cost savings between the first two is bigger than between the last two -- despite the same change in the number. Basically, every time you use mpg, you have to do a division -- not the hallmark of a convenient unit.

  3. Winter by Anonymous Coward · · Score: 5, Funny

    In the winter I leave my computers on. I don't think I am "loosing" any energy that way since it's used to heat my house.

    1. Re:Winter by Poltras · · Score: 5, Funny

      My dorm room used to get so goddamn hot because of this.

      Mine used to get hot because of the girls. Aaaah! Wishful thinking...

    2. Re:Winter by MrSteve007 · · Score: 5, Interesting

      The EPA awarded my company with one of their top awards this year for improvements to our facility, and energy efficiency. Overall we cut energy consumption 50%, but also used our energy more smartly, including a dedicated ducting system from our server room to the building entrances. We calculate that our servers put out between 8,000 & 12,000 Btu an hour. Most of our overnight heat now comes from the servers (which have to be on 24/7 for off site access), and we've reduced our server air conditioning loads by 80% annually. We're now beginning to implement this change into bank designs.

      In almost every application, it's ideal to shut off computers when not in use, but there are some business based situations where it makes sense to better harness waste heat from electronics, instead of fighting it with energy intensive air conditioners.

      http://www.energystar.gov/index.cfm?c=sb_success.sb_successstories2008_johnsonbraund

    3. Re:Winter by SydShamino · · Score: 5, Interesting

      None of that justifies heating with electrical resistive elements. There are two flaws to your argument:

      1. You mix using gas with whole-house heating.

      These shouldn't be mixed. You can have a whole-house gas furnace, or you can have gas units (or a gas fireplace) in critical rooms. Likewise, you can have a whole-house electrical system, or one per room. Or, you could have electronically-controlled baffles for your air distribution, which cost relatively little but allow you to direct airflow to only specific rooms at specific times of day.

      2. You are advocating resistive heating as efficient.

      Resistive heating can be 100% efficient: every watt you purchase becomes a watt of heat in your room (until it leaks out the window).

      But that's not efficient for heating. A heat pump uses the watt of energy you purchased to perform work, moving heat contained in the colder, outdoor air to the warmer, indoor air of your house. The net effect is that each watt you purchase can translate to 3-4 watts of heat in your room. While clearly not accurate syntax, a head-to-head comparison would call such a heat pump 300 to 400 percent efficient, significantly better than the mere 100% your resistive heater generates.

      Then you can use electronic baffle control to direct the heat just to bedrooms at night, and result in an overall system that is quite efficient and doesn't rely on one particular fossil fuel to function.

      disclaimers

      My house heats with natural gas, and we have an electric heat pad on our bed for cold nights. In other words, we do exactly the things I advocate against. That doesn't make them right, it just makes my actions wrong.

      --
      It doesn't hurt to be nice.
  4. Sorry I can't turn off my PC by theaveng · · Score: 5, Funny

    >>>"Turning off PCs during periods of inactivity can save companies between $25 and $75 per PC per year"

    How am I supposed to download last night's episodes of Smallville and Supernatural if I have my PC turned off during the day? Jeez. Insensitive clod. ;-)

    --
    FOX NEWS.com should be BANNED from television and internet. Have the Congress take it over and give us Truespeak.
    1. Re:Sorry I can't turn off my PC by Nursie · · Score: 5, Interesting

      NSLU2 + bus-powered USB drive + debian + torrentflux-b4rt

      Max 10W drain, with one drive it's nearer 5W. Add in ushare and you have a low energy box that has a web interface for torrenting stuff and can stream the results to your xbox. All for $60 (or so) and the price of the drive.

  5. I felt a disturbance in the Force . . . by PeeAitchPee · · Score: 5, Funny

    . . . as if millions of Folding@Home and Seti@Home clients suddenly cried out in terror and were suddenly silenced.

  6. Word by IceCreamGuy · · Score: 5, Informative

    All through college I left my PC on 24/7, however now that I'm paying the bill I have thermal throttling and the other new power-saving standards all turned on, and I turn everything off (router, modem and all) entirely when I'm not using it. It's odd the way people look at it; at work some users say "Well I never leave it on at night because I know that it makes the computer die quicker" and some people say "Well I never turn it off because I want it to last longer." I think the truth is that modern hardware really can handle both philosophies and it's just a matter of convenience vs. power costs at this point.

  7. Quoted from the article by genner · · Score: 5, Insightful

    "potential user complaints can be mitigated by communicating the positive financial and environmental benefits of PC power management."

    Now that just plain hilarious.

  8. No thanks to the spam by Pharmboy · · Score: 5, Insightful

    Learn how to save $25 to $75 by purchasing the $279 dollar report that the article is hawking. No thanks. This article has no business even being on Slashdot. It isn't news, it is an advert.

    --
    Tequila: It's not just for breakfast anymore!
  9. Typo? Pshaw! by ClayJar · · Score: 5, Informative

    Of the four instances in which watts were referenced (directly or in compound units), three are completely boneheadedly wrong:

    Forrester debunks this myth as follows: The average desktop draws 89 watts per hour. If it's left on overnight for 16 hours, it consumes 1.42kW. It's impossible for the power surge that occurs when powering on a PC to rival that figure: "You would be drawing energy at a rate of 17 kWh -- the equivalent of 44 HP DL580 servers at 100 percent utilization. Moreover, the average US wall outlet can only provide 1.8 kW of draw, which is about one-tenth of what the power surge would require."

    They should be:

    • 89 watts
    • 1.42 kWh
    • 17 kW
    • (1.8 kW is correct.)

    You *can't* call it a typo when they are perfectly backward in three out of four incidents. And you can't call it "They just got it backward..." when they got it right once. You must conclude, therefore, that they have almost no grasp whatsoever of units.

  10. Bad News For Vista by stewbacca · · Score: 5, Funny

    FTA: Modern computers are designed to handle 40,000 on/off cycles before failure

    With all the reboots required, that means I am limited to three Vista reinstalls?

  11. Re:Bad economics by Spazmania · · Score: 5, Insightful

    You're making the assumption that people work continuously whenever their computer is on

    I'm also assuming that you earn minimum wage. ;)

    --
    Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
  12. Re:Thats why you don't turn off, you sue S3 suspen by netsavior · · Score: 5, Insightful

    I have never had a PC or a Laptop which was able to reliably "Suspend" or "UnSuspend" Never in my life.

    Not with Windows or several Linux Distros. I would say at least 25% of the time the machine will not return and must be rebooted anyway.

  13. Do they care? by Moraelin · · Score: 5, Insightful

    From my experience with some corporations, the way it works is more like:

    1. The left hand doesn't know, and doesn't want to know what the right is doing. If your department can save $10 bucks, but it costs everyone else 10 million in workarounds and lost productivity, who cares? You're the greatest anyway.

    2. Any attempts to rein in waste and such effects, just introduces one more layer who'll get their bonus for making you buy a tool that costs $10 less, but where you spend 100,000 more in salaries to do the same job. Occasionally it introduces a masked form of corruption too: they get more bonus for buying a $1000 pencil at 50% discount, than a normal one at 5% discount. In the former case they "saved" $500 per pencil. They're that great.

    3. Don't underestimate interdepartment power games. Making you curse and waste more effort for implementing my hare-brained cost-cutting schemes, is the gretest achievement some people can get. It's me having power over you. For some people it's a powerful drug.

    4. Theatre. Being seen as doing something beats doing the right thing. You can see that at all levels and in all domains: security theatre, cost-saving theatre, etc. Being seen as being teh great green saviour can beat actually saving money.

    5. In that vein, beware the new boss who just has to piss on everything to mark his new territory. The higher level, the more dangerous. These guys _have_ to show that they changed something. It shows vision, leadership, etc. So he'll cheerfully make an actual loss, just so he can put a good leadership and vision theatre.

    6. There's a whole caste of people across the pyramid whose goal in life is to not rock the boat and not be responsible for anything. It's better to comply with a dumb rule (even one that wasn't supposed to apply to your situation or domain) than to have anything be your personal decision, and responsibility if it fails. Applying someone else's rule is like having a papal indulgence: whatever goes wrong, you're not the one who'll be punished for it. These fine guys and gals would mindlessly enforce even turning off the computers _during_ work hours, if that's what the rules say.

    7. Don't underestimate the effect of rewarding failure. E.g., see the thing about "saving" money by buying a disproportionately _more_ expensive thing. E.g., in some places, keeping the people under you from doing their job can mean needing to hire more people, and if you get enough of them you get a promotion. E.g., being the guy who dumbly applies rules without thinking, cam actually get one a promotion or at the very least it's often enough to not get demoted or phased out.

    So, yes, I've seen places where they paid consultants in the range of thousands per hour, but would rather pay those to twiddle their thumbs for a quarter of an hour while a baroque configuration starts, than "waste" cents on leaving that computer idle over night.

    --
    A polar bear is a cartesian bear after a coordinate transform.
  14. Re:Typo? Pshaw! by Anonymous Coward · · Score: 5, Funny

    It makes perfect sense. I just read it to mean that power usage increases every hour by 89 watts, and that by the time it's been left on overnight for 16 hours, the power usage of an average desktop has increased to 1.42kW. (If you think I'm joking, do the math -- that can't be a coincidence ;-))

    This kind of growth of power usage means it is extremely important to turn off your PC every night, otherwise by a month later the power consumption will be approximately 64kW, which will probably result in it melting through your desktop unless you have very good cooling.

  15. Re:Typo? Pshaw! by Anonymous Coward · · Score: 5, Funny

    This kind of growth of power usage means it is extremely important to turn off your PC every night, otherwise by a month later the power consumption will be approximately 64kW

    64kW should be enough for anybody.

  16. Re:Typo? Pshaw! by systemeng · · Score: 5, Interesting

    Unit errors are generally a sign in technical fields that a report hasn't been well thought out. No engineer proofreading this would have missed such a blatant error which means that an engineer didn't proofread it.

    If an engineer did not proofread it, an engineer did not likely do it. Therefore, the content of the article was likely done by an incompetent hack and charging $279 for the report is a way of hiding the fact that it was written by a hack.