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Hardware Hacking Power Upgrades Build

Reducing the Power Consumption of Overclocked PCs 119

babyshiori writes "Now, that must sound pretty inane. After all, overclockers employ all kinds of power-guzzling methods to improve their CPUs' overclockability. However, there are many good reasons to do so. In this guide, we will not just look at theoretical tips on reducing power consumption in overclocked PCs, we will also look at how well they work in real-life situations. Best of all, we are shown why they will improve our PCs' power efficiency without any real loss in performance. Start doing your part in saving the planet now!"
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Reducing the Power Consumption of Overclocked PCs

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  • by Anonymous Coward on Saturday May 03, 2008 @02:05PM (#23285336)
    Energy conservation isn't about saving the planet - the planet doesn't care. It's about saving humans. We'll all die out and the planet will quite happily go on without us.
    • Energy conservation isn't about saving the planet - the planet doesn't care. It's about saving humans. We'll all die out and the planet will quite happily go on without us.

      Actually, that's a common enough mistake for most people as to be forgivable. In the West, we have this notion that we're born "into this world" with an implicit assumption we're separate from (and possibly, above) it all.

      Asking people to view themselves as being "of this world" would allow people to see "the environment" as "our environ
  • by Anonymous Coward on Saturday May 03, 2008 @02:06PM (#23285352)
    It was going well until I got to 'I can save 13 megawatts per month'. Obviously this article was written by someone who has a deep technical understanding of power and energy consumption, and not just some kid who thinks he is a 'l33t haxor' because he found out how to use the utilities that come with the motherboard to turn his overclocking on and off.
    • Re: (Score:1, Informative)

      by Anonymous Coward

      I can save 13 megawatts per month

      Yes, somehow he's saving on average ~17.5kW/h. I'd love to know where he managed to dig up a 17000+W power supply...
    • I've got an EX38-DQ6 which features the Dynamic Energy Management, which is a feature that changes the power consumption of the CPU based on its current usage. Unfortunately, they measure the 'total saved power' in 'Watts', which as we all know, isn't the right way to measure energy consumption. I'd imagine whoever wrote the article got lured into the same trap somehow...
  • by Anonymous Coward
    WTF? There're tips there that saves the planet?
  • Saving the world (Score:5, Insightful)

    by maxume ( 22995 ) on Saturday May 03, 2008 @02:08PM (#23285358)
    If you are really worried about it and you drive, drive less.

    1 gallon of gasoline = 131 megajoules = ~36 kilowatt hours.

    Waving hands around about efficiency and so forth, that's 1 kilowatt hour of energy per mile driven. So that's 5-20 hours of computer use (assuming between 50 and 200 watts, 500 watts is still 2 hours) per mile driven. Using a more efficient computer is good, but finding a way to not drive 5 miles a day is a considerable amount better.

    (If you aren't worried about it, that's fine, but if you are worried about it, for god's sake, do the easy, effective things before you start telling people about the difficult, pretty much a wash things that you are doing.)
    • Re: (Score:3, Insightful)

      by CastrTroy ( 595695 )
      Another solution would be to get a cheap lowpower laptop and use that whenever you don't required the full power of your overclocked gaming rig. When you're playing games, if you really thing you need the power, then feel free to use it. Otherwise, if you're just browsing slashdot, a $500 laptop would probably do the job just as well.
      • Re: (Score:2, Insightful)

        On the other hand, think of all the energy that goes into producing all the new computers out there, from mining and refining the often-hazardous materials, to making chips, assembling circuit boards, packaging, and shipping. I can't do the math, but it might be more environmentally friendly to just stick with one computer that can do everything you could possibly want, than to buy two and alternate.

        The best solution I can think of (without completely ridding yourself of computing machines, and going off

        • Re:Saving the world (Score:5, Interesting)

          by DarkOx ( 621550 ) on Saturday May 03, 2008 @05:01PM (#23286388) Journal
          The other thing to consider is maybe we should look at increasing the lengh of the hardware life cycle rather then constantly cutting it. We should start demanding that software vendors start producing tight efficent code again so that we don't have to keep replacing our machines to use it. We should demand hardware vendors produce platforms that have a long life span with an upgrade path that enables most components to be resused as much and as long as possible.

          These is all speaking of primary systems.

          I had my first PC, and 386DX-20 for almost 10 years(MSDOS and later Windows 3.x added).
          My second system a Gateway P5-90 for about 5 years(MSDOS and Windows 3.x).
          My third system home built Cirix 8686-233 for about 3 years(Windows 95 and later 98)
          My fourth system home built K6-2-450 for about 2 years(Windows 2000, later Slackware 8 after ---------frustration with the performance of win2k)(would have kept it longer but it broke)
          My fifth system now about 8 years old Athlon-800 (Slackware 10.2 and now 12.0 I am even using compmgr on X and enjoying sexy transparent windows!) (works fine with my lowly geforce2-mx400)

          Scary trend in that propriety software world. Other then playing and encoding some video MPEG2 and 4 are fine some of the more recents ones are pretty slow to encode and difficulte to play back properly; I can do just about everthing as well with my 8 year old box as can be done with a brand new one. I chose software that is not wasteful and can thefore get allot of miles out of a machine now. I grant you I am not a PC gamer, I have a Wii for that. I am pretty confident the enviornmental impact of my having replaced this machine at least once if not more then once in the Commercial software world would have been greater then any questionable power efficencies of this older equipment, CRT included. The power draw of PCs has not exactly been trending down in general so its likely new gear would save little there at all if anthing the main offset being an LCD rather then the CRT.
          • by maxume ( 22995 )
            I went from the family Apple IIe to the family 486 running Win3.1, to my first computer, a Pentium II 333 running win98 and then win2k, to this laptop, a core duo 1666 with XP. Power consumption went up with the 486, probably stayed about even with the PII and took a nosedive with the laptop. I had the PII for 8 or 9 years(or used it, it's sitting right over there), the laptop is at 1.5 out of what is hopefully at least 4 years.

            It's likely I will replace it with a laptop(not a gamer, so why not...), I don't
          • Gee, not for nothing, but you'd probably have to upgrade a LOT less if you didn't buy shitty hardware to begin with. I mean, seriously, you are getting what you paid for. I mean, CYRIX? Jesus.
        • Re: (Score:3, Insightful)

          Comment removed based on user account deletion
        • The best solution I can think of (without completely ridding yourself of computing machines, and going off to milk some cows) is to satisfy yourself with a single, old laptop that you bought used. But who on Slashdot would do that? I know I couldn't.

          If you just want another computer to use to browse the web, an even better solution would be to dumpster dive an old P3 system, or something like that. I've gotten pretty high end P3's from the trash (1Ghz, 512MB, 40GB) which would be more than enough to browse
      • Re: (Score:2, Insightful)

        by Anonymous Coward
        $500 buys you a lot of kWh. Buying a second computer will likely cost you more money than you'll save. From a "green" point of view, you have to compare the environmental impact of the extra kWh you're consuming vs the environmental impact of producing a laptop. Again, most likely the extra kWh are a better choice.
      • I prefer to eat a lot of meat, go on lots of joyrides, and burning a lot of brushwood from our semi-wooded yard. You see, we were going to move to North Carolina from Pittsburgh, but I figure it will be a lot less cheaper for me to just create as much volume of greenhouse gasses that I can so that global warming will just move the NC climate up this way.
    • by jadin ( 65295 )
      My problem with comments like yours is that there's nowhere saying you can't do both. Just because you 'help the environment' in one way, doesn't mean it's exclusive.
    • One, it may not be possible to drive less. It's easy to tell someone "Oh just drive less" but what if (as with many people), their daily drive is to work? It isn't as though it is trivial to just find someplace to work closer to where you live, or move closer to your work.

      The second is that just because cars are the biggest user of energy, doesn't mean it is worthless to optimise where you can. Lightbulbs are a good example. They really aren't that big a power user over all. Your average incandescent lightb
      • by maxume ( 22995 )
        I don't really think I said not to worry about the little things. I said(or rather, implied) that talking up the little things while ignoring the big things is inane.

        Moving into a larger house that is further away from work and then going on about how great the energy savings from CFLs are is the kind of thing I am talking about. Figuring out how to live 15 miles closer to work is going to save 5 gallons of gas a week. CFLs conversion won't even touch that(~600kWh/month). Sure, it's good to make savings whe
      • Lighting is around 1/5th of US electricity production, of that, around half is for commercial lighting, residential about a quarter. Here is a semi recent breakdown US lighting stats [energy.gov]

        I wonder how much of that commercial figure is for..well.. for spam signage burning all night? I live out in the medium sticks but whenever I go to town that is the huge impression I get, tons of "buy me-acme stuff!" signs running all night long, even when the store/business isn't open. I also *seriously* question the business c
    • Good point, but think about all the energy (for data transmission, writing to disk, reading from disk many times over and client-side rendering) that could have been saved if you hadn't made that post.

      Did I get your point? :D
  • by Dr.Diesel ( 812427 ) on Saturday May 03, 2008 @02:09PM (#23285366)
    He is saving 26megawatts per month? I didn't know Intel made 13.8KV 3-phase E6850s?
    • maybe he has a really good overclock running at 40V
    • Re: (Score:3, Funny)

      by evanbd ( 210358 )
      We're talking about an overclocked CPU. He upped the voltage, and it draws more current now. What, you thought the cooling tower in the driveway was for show?
    • If I could store that energy in 39 months (roughly) I'd have 1.1 gigawatts. My options would be to get a substantially better computer from the future or go in the past and correct this post if my math is off.
    • Silly Slashdotter, the savings comes from powering down the flux capacitors. Don't you know ANYthing about science?!?! Geez, next you'll say reducing carbon dioxide makes the planet more green. Any fool knows plants breathe carbon dioxide. Reducing it makes the planet more BROWN!
  • by Anonymous Coward on Saturday May 03, 2008 @02:10PM (#23285372)
    I've been hearing a lot of this kind of fluff during earth week.

    If you really wanted to save the planet, you wouldn't be overclocking your computer at all or buying a new car because it was hyrid. You would be beating what you have already consumed until it fell apart from overuse.

    Most of these "earth saving" techniques seem like nothing more than feel good consumerism. Eco this and green that. Nothing more than words.

    And if your computer was burning 24/7 in the development of new energy technologies or new effiencies you would really be saving the planet. And all these real efforts at saving the planet are going to require technology and huge amounts of energy use and chemicals and industry and all that supposedly evil stuff.

     
    • Re: (Score:3, Informative)

      by Burz ( 138833 )
      However, the article doesn't have any elements that would entice the reader to buy more stuff. He's not very pointed about it, but is essentially saying that if you need the processing power then moderate overclocking is a pretty 'green' option.

      Some people on the CPDN forums track their system efficiency in terms of work units per Watt-hour and have noted the dramatic increase in efficiency in opting for a quad-core CPU even over a dual. TFA's advice has a lesser but similar effect and I would recommend it
    • Re: (Score:3, Insightful)

      by Spoke ( 6112 )

      If you really wanted to save the planet, you wouldn't be overclocking your computer at all or buying a new car because it was hyrid. You would be beating what you have already consumed until it fell apart from overuse.

      Unfortunately, it isn't always better to beat what you have already consumed until it falls apart. Whether or not it's better to beat something into the ground until it is not longer usable or repairable or to buy the latest high efficiency model depends on:

      1. The impact of manufacturing said item.
      2. How many fewer resources said item consumes during use.

      This analysis is called a life cycle analysis.

      For example, your typical computer consumes much more energy during manufacture than during use. So for this

    • by AK Marc ( 707885 )
      If you really wanted to save the planet, you wouldn't be overclocking your computer at all or buying a new car because it was hyrid. You would be beating what you have already consumed until it fell apart from overuse.

      Why? When I buy a car, the one I trade in isn't destroyed. If I don't buy a car, someone else will. The number of cars on the road is growing relatively steadily. So the choice is whether I buy a fuel efficient car, passing along my old car to someone else that will use it until it will
      • Except... someone would've bought a car no matter what, just not the specific one that you bought.

        So, by not buying a car, you ARE reducing the demand for new cars, which in turn reduces the production.
        • by AK Marc ( 707885 )
          Except... someone would've bought a car no matter what, just not the specific one that you bought.

          Exactly what I said.

          So, by not buying a car, you ARE reducing the demand for new cars, which in turn reduces the production.

          That's not a true statement if demand is flat. You can't increase used cars and decrease new cars. The used cars have to be new first. With inelastic demand for "cars" (new or used) only if a used car is destroyed or a new car sold does the number of cars change, and the demand in
          • Ah, but often, used cars are crushed because of minor repairs that are more than the car's value.

            If there's less demand for new cars (which, in this example, would translate to more demand for used cars,) the value of used cars would go up, and it would make more sense to maintain those used cars.

            Also, one could elect to just maintain the used car despite the repairs being more than the car's value, due to it still having a lower TCO than a new car, but nobody thinks about that here.
    • Not quite.

      I just replaced 3 9-year-old servers with bvrand-new hardware and the temperature in the server room actually dropped a few degrees.
      (each of those 3 servers consumed more than the 4 new ones combined)

      New cars pollute a LOT less than old ones.
      If you want to stop carbon emissions, you would rip out the engine of the very old cars and put in a new, efficient one.
      Maybe install a a catalyst in your old car or carbon filter on that old Diesel.
      Failing that, return the old car and make sure your manufactu
  • by Anonymous Coward on Saturday May 03, 2008 @02:10PM (#23285376)
    Improving the gas efficiency of your Humvee using proper tire inflation.
  • Thanks to my overclocked PC running at a super high core voltage. w00t!
  • by theurge14 ( 820596 ) on Saturday May 03, 2008 @02:15PM (#23285402)
    * Set your desktop background to something like penguins or polar bears
    * Install a screensaver with air conditioning capability.
    * Set your beer on top of the case so the cold will seep down into the computer.
    * Type slower as fast typing causes heat friction. Also avoid CAPS and waving the mouse pointer around too much.
    * Use a lighter color scheme on the desktop instead of dark as dark colors absorb light and generate heat.
  • slashdotted. Slashdot should have a mirror site so this doesnt happen so often.
    • Re: (Score:1, Informative)

      by Anonymous Coward
      it's no loss, the article was crap
      • Re: (Score:3, Insightful)

        by nigelo ( 30096 )
        Summary:

        Save power on your overclocked PC by not overclocking it.

        Also, reducing the power consumption of your PC will reduce the power consumption of your PC by JiggaWatts per Fortnight.

        Conclusion:
        A meaningful way to save power/money is:
        Turn off your computer at the power strip, and go out for a conditioning bike-ride, and be ready to bike-commute.
        Certainly, do not waste your time using your computer to complain about not being able to read the article.

        "Read the article" - what are you thinking?
  • There is often one in a family. Remember the 1.13Ghz PIII, the AMD x64. Right now it is the 45nm Core2Duo [wolfdale] processors.

    Target undervolting 10% and OC the FSB about 10%. Of course turn on the energy saving features like the C1E reported in the story.

  • FTA

    Increasing the voltage by 500 MHz to 3.9 GHz

    volts are J/C thank you very much
  • 80 Plus (Score:5, Informative)

    by Hatta ( 162192 ) on Saturday May 03, 2008 @02:28PM (#23285478) Journal
    He didn't mention 80 Plus [80plus.org] power supplies. Not only will you save power, your case will be cooler.
  • Does overclocking indeed improve the performance? Unless you can show that the CPU clock freq. is the true bottleneck of your computing tasks. Often it is not so. Clock rate != performance and vice versa.

    For most users the CPU works just fine out of the box. My laptop with a Pentium-M class chip even works underclocked by default to reduce power usage. BTW, it runs Linux of course.

    I hope the whole overclocking thing could be stopped if you care about energy consumption.

    There's a classical joke that the

    • by Belial6 ( 794905 )
      I can tell you that my system is CPU bound a lot. Of course, If I increased the speed of my CPU by 10% by overclocking, it would still be CPU bound, and getting a task done in 54 minutes instead of 60 isn't really worth the effort of overclocking. This is particularly true when it comes to the kinds of things that take an hour to run since I will likely not be sitting and watching my screen count down for an hour anyways.
    • It's pretty application dependent. For most desktop usage, more clocks aren't too useful, but for video encoding, gaming, and such, CPU performance is the limiting factor.

      I'm running my E2140 (stock 1.6 GHz) at 2.8 GHz. I'd say it's a worthwhile overclock.
    • I only ever noticed a speed increase when overclocking video cards back years ago. If your Quake is only getting 20fps in 1024x768, the extra 5fps was kind of key to comfort playing.

      Nowadays, it's just stupid. If you are getting 80fps at 1600x1200 with FSAA, you won't notice an extra 10fps. People will swear it makes a difference, but I don't see it.

      I'll tell you why overclock features are present: It's because of the kiddy kulture regarding the practice. If you toast your video card, mobo, cpu, etc -- you'
  • Not so silly (Score:4, Interesting)

    by NMerriam ( 15122 ) <NMerriam@artboy.org> on Saturday May 03, 2008 @02:32PM (#23285496) Homepage
    I don't know why people are being so negative about this article. It isn't trying to convince you that overclocking is the most energy efficient thing to do, it's trying to show you ways you can be more energy efficient if you do choose to overclock. People who overlock do so because they want higher PEAK performance, not because they enjoy wasting energy 24/7. When you're not in need of that peak performance, it only makes sense to go ahead and be efficient.

    The whole article can be summed up by saying:

    1) Be sure to enable whatever idle tech your motherboard/processor supports (speedstep, cool'n'quiet) so that it automatically slows down the CPU and power consumption when not under load.

    2) Try undervolting, use stability tests to find the lowest voltage your particular CPU can use, rather than simply using the default.

    3) If your motherboard/processor comes with some software that lets you configure the clock speed/voltage on-the-fly, go ahead and test stability under different settings and save those configurations and use them when appropriately. I'd add that most video cards have the same type of software these days -- go ahead and overclock them when you're gaming, and be sure to slow them back down when you're done.

    Neither of those should be shockingly new ideas to anyone who's been building computers for years, but anyone new to it should find the article informative in the specifics.
    • Re:Not so silly (Score:5, Informative)

      by Zadaz ( 950521 ) on Saturday May 03, 2008 @02:55PM (#23285624)
      People are so hard on this article because, for the effort it's taken to write it, the author could have gone outside and planted a tree and done much much more for the environment in total than this article ever will.
      • by NMerriam ( 15122 )
        Yeah, and it would have been more energy-efficient for Al Gore to tend a compost heap than fly around the world giving lectures, but the question is whether he convinced enough other people to make changes to offset the opportunity cost he missed. If 100 people read the linked article over the next 5 years and change some BIOS settings, that's a lot bigger global payoff than anything the author could have done in the hour it took him to write.

        Human societies practice specialization, and someone doing what t
    • People who overlock do so because they want higher PEAK performance, not because they enjoy wasting energy 24/7.

      Just about everyone I've known who's been around computers their whole life think overclocking is pretty stupid nowadays.

      Sure, there was a day when you could run a 25Mhz cpu at 33Mhz and see a big jump in performance, but now you can just a couple of percentage points because the tolerances are much tighter.

      Plus, unless you are buying the absolute fastest, super dooper extreeeeeeme edition multi-cored CPU, the cooling system will probably cost more than just plunking down for the faster processor to begin

      • by NMerriam ( 15122 )
        Well I'm definitely past the age where overclocking is anything exciting, but it does seem like some of the current Core2 processors are much more overclock-friendly than anything we've seen in years. Getting a 2.0GHz part to run at 3.0GHz is pretty significant for your average college gamer on a budget, and isn't a crazy unusual type of performance gain based on my perusal of Newegg testimonials when building my last system. I got the impression that 20-30% clock speed with standard cooling was practically
    • I think the point many people are making is that if one is concerned about it enough to take these steps for very minute power savings then maybe they should just not overclock at all, or, you know, turn off the computer when you aren't using it.
    • >>1) Be sure to enable whatever idle tech your motherboard/processor supports (speedstep, cool'n'quiet) so that it automatically slows down the CPU and power consumption when not under load.

      Which doesn't work with overclocking on most mobos.

      >>2) Try undervolting, use stability tests to find the lowest voltage your particular CPU can use, rather than simply using the default.

      Which doesn't work with overclocking on most setups. OCing usually requires you to raise the voltage.

      >>3) If your mot
      • by NMerriam ( 15122 )
        I think you need a new MoBo. Speedstep and Cool'n'Quiet don't care what the FSB or core are set at, they just switch to some fraction of that frequency when the load allows.

        Yes, OC usually requires you to raise the voltage. But there is still some minimal voltage for any given frequency at which the system will run stable. Using that voltage and no more is an efficient move. No need to up the voltage by .5 if .2 will do the job.

        It's impractical to use the simple software that most modern motherboards and GP
        • I've built 4 machines over the last couple years, and all of them required Cool N'Quiet to be disabled in order to overclock.

          And yeah, it's pretty impractical to set a voltage that will work for normal load, but crash your system if you load it.
  • If the thermal load per square cm of a cpu is as hot a a nuclear reactor why don't we use them as hot water heaters? Cold water to cool the cpu hot water out to wash my filthy ass.
  • summary... (Score:2, Funny)

    by Anonymous Coward
    1) use speed stepping
    2) don't overclock as much

    wow, great article!
  • Just in case you read TFA. It states that "When running at full 3.9 GHz, I would save about 26 megawatts a month. Sweet!"
    This is incorrect.
    26 megawatt is the energy consumption of a medium sized city. Units for saving should in any case be watts, or kilowatthours per month to make it easier to convert to $$$. (note that this is again just watts multiplied by a constant: "kilo" and "hours/month")
  • by leuk_he ( 194174 ) on Saturday May 03, 2008 @05:32PM (#23286542) Homepage Journal
    If your fan runs faster, your cpu temperature is lower, resulting in less current leakage.
  • The only reason I want to save energy is because it costs money. I don't drive a small car because I like it, but because it is not $100 per tank. Global warming is a hoax; just something the liberal media has conjured up by twisting the facts around. If you put the time and effort into the research, you will see exactly what I mean. Polar bears are dieing off because their population is at an all time high and their food supply has remained the same. P.S. they are not friendly and cuddly toy bears!
  • I heat my house in Winter using my overclocked PC.

    I'm sure that I'm saving quite a lot of energy compared to traditional heating systems. :D
  • I have enabled Gigabyte's on-demand FSB overclocking BIOS option which allows the CPU & memory to work in low FSB (233 Mhz) on most tasks and high FSB (280 Mhz) at high usage.

    I have also used RivaTuner to reduce my graphics card's GPU core and shader clocks as well as memory clocks to very low levels when the memory of the card is at low usage levels and to get it back to normal when more than 128MB of video memory is being used. This is better than nVidia's automatic clock adjustments because nVidia re
  • Surely using Stand By would be a more effective method for saving power while a system is idle. It's much easier to configure and I'd imagine would save a hell of a lot more power. This is assuming the article author defines 'idle' as not being used.

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