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Power Hardware

First Actual CPU Energy Use Statistics Published 103

Posted by Zonk
from the stats-for-science dept.
BBCWatcher writes "CNN is reporting that the U.S. Environmental Protection Agency in August asked server manufacturers to develop 'miles per gallon' ratings for their equipment that would provide accurate assessments of energy efficiency. IBM says it is now providing 'typical usage ratings' for its line of z9 mainframe computers, in addition to previously available maximum power ratings. More than 1,000 z9s around the world started reporting (with the owners' permission) on May 11th their actual installed power and cooling demands, so IBM can publish statistics such as how much energy is required to turn on an additional processor to run multiple Linux virtual servers. The answer? About 20 total watts. 'Over time every vendor is going to be asked to provide typical energy use numbers for their equipment. It's what the EPA wants, and this allows us to move beyond simple performance benchmarking to energy benchmarking.'"
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First Actual CPU Energy Use Statistics Published

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  • damn lies (Score:2, Interesting)

    by Bob-taro (996889)
    Oh, but there are so many ways to play with statistics. Hey, is the the first post?
    • Re:damn lies (Score:4, Interesting)

      by Bob-taro (996889) on Friday October 12, 2007 @12:23PM (#20955645)

      Ha! I confess, I cut that post short to try to get the first post (I'd never gotten one before!)

      Anyway, the problem with trying to get some "miles per gallon" efficiency rating on computers is defining the "miles". For example, if computer A is 2 times faster and uses 1.5 times the energy compared to computer B at full load, and both computers are run at full load 8 hrs a day (doing some serious number crunching), which computer is more efficient? A is using more power, but is doing twice the amount of "work" of B. So do you measure straight Watts? Watts / MFLOPS? If you use MFLOPS, how do you account for differences in architecture?

      • by Runesabre (732910)
        I see what you're saying and definitely would be suspectful of a rating that included speed and energy consumption all rolled into a single number.

        I see this as another important rating to be used simply to evaluate a chip based purely on energy consumption. It should also be a good motivator for chip makers who haven't concerned themselves with energy consumption when their chip suddenly is viewed unfavorable when compared to more energy efficient yet equal performing chips from rivals.

        Most IT purchasers
      • by Reziac (43301) *
        I suppose you just run the numbers, same as for anything else.

        Example which by unfortunate chance is handy: I have to replace my well pump. I can either go with a 10 horsepower pump that does 60 gallons per minute, or a 3 horsepower pump that does 18 gallons per minute and costs about $1000 less up front. Now, 10HP uses one helluva lot more electricity than 3HP... but it only needs to run a fraction as much time to pump the same water. Turns out when we ran the numbers, the 10HP was actually more cost-effec
      • by pz (113803)
        Anyway, the problem with trying to get some "miles per gallon" efficiency rating on computers is defining the "miles". For example, if computer A is 2 times faster and uses 1.5 times the energy compared to computer B at full load, and both computers are run at full load 8 hrs a day (doing some serious number crunching), which computer is more efficient? A is using more power, but is doing twice the amount of "work" of B. So do you measure straight Watts? Watts / MFLOPS? If you use MFLOPS, how do you account
      • by dj245 (732906) on Friday October 12, 2007 @02:36PM (#20957965) Homepage
        In the marine diesel engine industry, there is a measurement of NOx (nitrous oxides), usually measured in grams per killawatt-hour (g/kW-hr). But not all engines will be used in the same service, so they won't be running at the same load. Some will run at 100% load most of the time they are on (generators, fire pumps maybe) while others will run at about 65 or 75% of full power all of the time- these are your direct-drive propulsion diesels. These different duty cycles have a dramatic effect on the numbers. So what to do?

        The International Maritime Organization has created a few different cycles- E2 is Constant Speed Main Propulsion, E3 is Propellor law operated propulsion for example. You pick your cycle, run your engine at a variety of loads, then use weighted averaging on those loads to determine what the emissions would be if the engine ran at E2 all the time. Then you can say that for the E2 cycle, the engine puts out so much NOx.

        For computers, someone needs to come up with some different computer cycles. There may be several of them- 50% parallelizable with 25% floating point and 75% integer math, 100% parallelizable with 100% floating point math, etc. Different architectures may take dramatically longer to do floating point or non-parallizable workloads. Only then could you run a bunch of tests and really say that under this load the computer uses this much power to do a certain amount of work in a given amount of time.

        This is not new or novel stuff. This is similar to how the EPA tests cars. Some cars do highway miles much better than city miles, so they do both and weight the averages.
      • The results in terms of a car are miles/kilometres travelled. In terms of computers, MIPS or MFLOPS are however not results, they are performance measurements. Using them would be like describing car efficiency in RPM per gallon. Not the results you're after.

        So the first thing to do is define what your results are. The results computers produce are the "bits of information you want".

        SPEC and TPC both have benchmarks which already attempt to describe the results that customers are after. []
        h []
    • Re:damn lies (Score:5, Insightful)

      by Colin Smith (2679) on Friday October 12, 2007 @12:28PM (#20955747)

      Oh, but there are so many ways to play with statistics
      All the more reason to understand how they work.
    • by blindd0t (855876)
      Good point. I think we can all attest that the 'mpg' analogy isn't so good in its present state, as it has been highly inaccurate in many (if not most) recent cases. Perhaps a simple energy benchmark similar to audio amplifiers would suffice: show me peak & continuous power. If it's on, what does it consume continuously (or as a minimum - i.e. just 'on' but idle), and what is the most it could possibly consume at any given time? I know this doesn't cover efficiency very well (i.e. watts/FLOP); howev
    • Re: (Score:3, Informative)

      by vtscott (1089271)
      I agree. While this could be a useful measure, companies will find ways to game the system like they always do. The problem is, if they just publish hard numbers and exact specs they will be difficult to interpret. When they publish these "more useful" stats, they'll just do everything they can to get the biggest (or smallest) numbers while sacrificing everything else.

      For example... I was recently shopping for home theater projectors and was doing a lot of comparisons between brands. The two most

      • by edmudama (155475)
        In many industries, this eventually gets resolved as the manufacturers realize that everyone is gaming the system, so they define new metrics that are perhaps harder to game, to help distinguish the quality of their products.

        One example would be the move from "response time" in LCD panels, to "grey to grey response time" which prevents advertising of just one of the hyperfast transitions. (Can't remember whether black-to-white or white-to-black is the faster one)
    • Like it costs The Dalles Google Center about $10/year at current hydropower prices to turn on an extra processor?
  • about time. energy prices aren't going down any time soon, and if this means a spread to accurate energy consumption cost reporting for all computer equipment, that can only be good news.
    • Re: (Score:3, Interesting)

      by Rei (128717)
      I agree. For those with home servers like me who leave their computers on all the time, I'd be willing to pay an extra $5 or so per watt saved ($2 for the price extra watt over the course of an assumed usage lifespan of 3 years, $1 for the reduced cooling cost and increase in part lifespan from it being cooler, and $2 extra for the environmental benefit). If I lived in a place with expensive power, like California, that would probably be $7 or so per watt saved.
    • Yes it's great that EPA is working with industry to get some more meaningful power ratings of computer equipment. But it's not easy to give "typical" energy use. What's typical gas mileage of your car? Does a 25 MPG EPA rating mean you'll get 25 MPG? How heavy is your foot, where do you drive, how far, how hilly, how many stoplights, etc.?

      From the SPEC power benchmark [] you'll get not just a single composite number, but all the details so you can judge what is most relevant to your own system. Is it idle mo

  • I would be interested in seeing statistics from the 80's on, to show how much power an "average" home PC or business workstation consumes. Over the years I've heard things like "it takes more energy to power it on than to just let it run", "it uses as much energy as a blowdryer", and "it uses as much energy as a lightbulb". Also, doesn't it take LOTS more energy to continually refresh RAM than it does to enable a processor? Think we could break usage down by component in these stats?

    Cheers, Securityf

    • by Trinn (523103)
      No it does not take more energy to refresh the ram. Here's how to tell that. The ram is built on the *same* process & technology (or perhaps even an older process, making it *less* efficient) yet it never gets hot enough to require a heatsink let alone active cooling. Given the same or less efficient process, the same portion of the energy pumped into the system would get turned into heat.
      • by nschubach (922175)
        ...but my memory does have a heat sink. Well, they are heat spreaders, but it's a similar concept. Move the hot to the cold.
    • by redleaf8 (894893)
      Just get a Kill-A-Watt []. My desktops use about the same power as a lamp with a 75 watt bulb in it, my laptop is 20-30 watts.
    • by archen (447353)
      "it takes more energy to power it on than to just let it run"

      I'm not sure where people get that from (I've heard it myself). Most of my tests on a run of the mill PC (onboard VGA) shows a computer drawing around 80W. There is a small spike when booting, but I honestly have a hard time believing you save money letting the thing run over 10 minutes. As someone else said, get a kill-o-watt and test it out. It's actually really interesting to see how much power stuff like TVs draw, as well as the difference
      • Is that 80W when the computer is in it S3 sleep state, or just idle at the desktop?
      • I'm not sure where people get that from

        It was defintiley true in the days of thermionic valves - ie the 1950's. It probably has not been true since the transistor was in common use for logic - approximately 1968 if my memory is correct (highly improbable).

        My profesiosnal testing shows that unless you havbe very expensive professional equipment, your readings are probably +/- 30% accuracy. Kill-a-watt is not expensive professional industrial test equipment.

        If you are concerned about server power consump

        • ...If you DONT run a datacentre, stuff the CPU, look at your AC costs! Who cares if the processor is taking 50W or 58W when your AC is using 3kW!...

          Pentium I, II and 3's run in the sub 75W range. I've read acticles which claim that Pentium 4's and the multicores processors chew up anywhere from 125W to 300W simply by idling. I have to guess that someone running a P4 with Vista is sucking up 300 watts, and when they play Halo, the consumption probably hits 500 watts.
          • by darthflo (1095225)
            Someone with a Pentium 4 will probably not even /have/ a PSU capable of delivering 500 watts. Afaik the worst P4 consumed 120 Most current desktops do have power-saving features, so I'd guess an office box would consume about a hundred watts on average, while really bad gaming rigs with two or more GPUs, a PPU and a dual- or quadcore processor should come in at around 300 average and up to 600 peak.
            • by billcopc (196330)
              Your guess is just about right.

              I've recently optimized my home power consumption, after my last PC upgrade caused the breakers to blow repeatedly. Here's the breakdown of my various PCs:

              Pentium Pro 200mhz (firewall/router) : 40w (no difference under load)
              AMD Athlon X2 3800+, underclocked to 950mhz (file server) : 100w idle, 120w load (with 8 hard drives)
              Dell 22" entry-level LCD : 45w in-use, 1w standby
              Viewsonic 19" CRT : 40w in-use, 1w standby (surprising!)

              And finally, my new baby. An Intel Quad-core Q660
              • by ratboy666 (104074)
                I use a dual PPRO 200 for routing, web serving, mail. Consumption is under 80 watts. For RAID file server, I pressed an IBM GL300 (266 Mhz Pentium II) into service. Only 4 drives at present, though. Seems fully capable of saturating the cable, so I haven't felt the need to replace it (although I have been looking at some lower power systems).

                My biggest problem is the MythTV box. Can't for the life of me get the thing to respond to a wake-on-lan packet (the mainboard claims the capability). As a result, the
        • by archen (447353)
          Actually I wasn't testing the datacenter (which uses vastly more power even when idle). I was testing desktop PCs. Many people at the company I work for tend to leave their PCs on all the time. Generally that bothered me as being wasteful, so I started to set many PCs to turn themselves off an hour or so after everyone left. I started to get some resistance when people complained that they had to turn their PC back on in the morning (yeah, tough life I know).

          So I started probing into how much power we w
    • by timeOday (582209)

      Also, doesn't it take LOTS more energy to continually refresh RAM than it does to enable a processor?

      Your best window into this issue is laptops, where every watt counts. The simple answer to that particular question is "no." I have a D630 Dell laptop with 4GB RAM. When suspended to RAM, it consumes about 1% of a 56 watt-hour battery, per hour. In contrast, with the processor and screen running the whole battery is emptied in 3 hours.

      Here [] is the sort of chart you're looking for, although it's somew

    • Get a WattsUp? Pro (from think geek...).

      My dual-core Athlon MythTV server uses 95 watts at the peak use I'm making of it. Start up current spike is pretty high, but the "costs more to run it than to power it on" line is complete BS. I can measure - don't have to assume.

      Running my server 24x7 would be like powering a 100 watt light bulb 24x7. It's not a perfect analogy - the server uses energy in a much more complex way than the simple resistive load of a light bulb - but it is a USEFUL analogy. Gets you to
  • by pigiron (104729) on Friday October 12, 2007 @12:13PM (#20955421) Homepage
    I'm sure it's true that adding additional virtual servers is only 20 watts. But that first one is a real whopper!
    • IBM mainframes look like some kind of warp reactor. I thought they produced their own energy!

      Seriously though... We had a z800 [] swapped out with a z9 [] at work. It looked like IBM added a supercharger and changed warp core elements.
      • by hey! (33014)
        Seriously, if you are going to charge a customer what it takes to buy one of these things, it's not that much additional effort to make it look cool. In this case like the love child of the 2001 monolith and a coke machine.
  • by Lookin4Trouble (1112649) on Friday October 12, 2007 @12:14PM (#20955437)
    How about getting a realistic number for BTUs of cooling per HDD/stick of RAM/Processor? my 31 year old Liebert is dying, and the time has come to go to in-row rack-standing AC, but I don't know whether to stick to 2x10Ton or if I need to go for a 3x10 (underfloor in a small datacenter - 30 racks, 250ish nodes). I realize manufacturers have whitepapers out on how much cooling is recommended, but those numbers lie like dogs. "Typical installation: 1 processor, 1 stick of ram, 1 HDD, 1 Power supply" - typical config for my cluster is 4 processors, 8 sticks of RAM, and 2 HDDs on dual power supplies... anyone know where I could get this type of info besides Gartner or the like subscription $ervice$ (yep, they get you coming AND going)
    • by guruevi (827432)
      Given that you are a small shop, you probably get a detailed energy bill on a monthly basis (not like you're buying bulk energy and nobody's really counting). A little bit of smart engineering would've made sure that you do have a separate counter for your datacenter or some kind of ampmeter where you can calculate what you're actually using (APC power switches in your racks have fairly accurate readings (always round up though)) since you're probably charging your customers depending on their usage.

      Since y
      • thanks, but I am looking to expand (always get more than you need, unless budget constrains, which it does)

        Speaking of which, I didn't engineer the room - it has been in place 21 years and I've been here all of 5, and all of the energy bills go to someone else.

        The Liebert unit in question is rated 20 tons, but I suspect that age and failing parts have pushed it lower than that, and my average temp rises about .1F/month (72.2F last month)

        I suspect that I could get by on 20T (120KBTU/hr), but I'd like to h

    • by gregor-e (136142)
      If you isolate the power going to your racks from that going to your cooling, can't you simply clamp an ammeter around the power cables going to your racks and assume that every watt going in turns to heat, then multiply watts by 3.4 to get btu/hr cooling?
      • If you isolate the power going to your racks from that going to your cooling, can't you simply clamp an ammeter around the power cables going to your racks and assume that every watt going in turns to heat, then multiply watts by 3.4 to get btu/hr cooling?

        Unfortunately, not quite that easy.

        1 * 3-phase powers the Air Conditioning (how much of this is really leaking back into the room as heat?!?)

        2 * 3-phase powers the UPS/Generator solution, which continually cycles batteries, changing the load on the li

        • by autocracy (192714)
          Well, since the compressor motor is on the outside of the server room, and is the primary consumer of energy, I'm going to say the answer is: "A small portion."
          • Well, since the compressor motor is on the outside of the server room, and is the primary consumer of energy, I'm going to say the answer is: "A small portion."

            ermm... not exactly. Remember we are talking 31-year-old tech here. Compressor motor == in the main cabinet (takes up about 6 racks worth of floor space)

            The only pieces not in the room are piping to/from and the radiator grid.

            • Well, then you have an additional variable. Pulling the compressor out of the room could let you put more servers in without changing the wattage. You'll have to calculate that change yourself though.
    • by An dochasac (591582) on Friday October 12, 2007 @12:51PM (#20956139)

      While it's a baby step in the right direction, Watts alone as a "benchmark" is meaningless as is Watts/CPU. The VIC-20 likely beat the Z9 back in 1980.

      If IBM is serious about server energy consumption, they should publish statistics using the SWaP (Space Watts and Performance) benchmark Sun has been promoting for several years or even "MFLOPS/Watt" or "Page serves/second/Watt" If the Z9 can handle a typical highly threaded webserver load with fewer watts than something like Sun's T2000 Niagara while providing identical performance, IBM shouldn't be afraid to prove it.

      Until then, I'll assume it's just another useless benchmark configured specifically to make IBM's products look better than its competitors.

    • by Chalex (71702)
      Just get a node like that and run your software and measure the power utilization, no? E.g. our IBM 1U nodes: x3550 (4 cores, all RAM full, 2 HDs, 1 PSU) use up ~460W each at full CPU + I/O load.
    • by imsabbel (611519)
      Every single component shows how much it will heat up your place. Its this little number with the "W" at the end.

      Why the hell you guys need two tollay different units for the same (Power) still eludes me, but i guess you just cant drop one with "british" in it...
      • Every single component shows how much it will heat up your place. Its this little number with the "W" at the end.

        Why the hell you guys need two tollay different units for the same (Power) still eludes me, but i guess you just cant drop one with "british" in it...

        So very, very wrong. W for Watt just shows how much power draw. What I'm interested in is BTUs of Heat output. A processor that uses 20W with 100% efficiency will put out 0 BTUs of heat, while a processor that consumes 70W with 20% efficiency

        • by j79zlr (930600)
          It is basically all converted to heat. There is very little energy consumed in data center equipment for light, sound or mechanical movement. Electrical energy in = heat out.
      • Every single component shows how much it will heat up your place. Its this little number with the "W" at the end.
        The Watts on the component is nominal load, you can ony use it to calculate start-up currents, and the rating of the fuses.
        The typical load during use (even at full speed) is usually much lower.
    • by j79zlr (930600)
      I am a mechanical engineer and design HVAC systems. I do not specialize in data centers, but most hospitals, schools and offices nowadays have data rooms. What we would typically do is provide cooling for the amount of power you have. For example, if you have ten 20A 120V receptacles feeding your equipment, then the cooling system should be designed for 10 X 20A X 120V X 3.41 BTU/hr per Watt equaling 81,912 BTUH or around 7 tons.

      Make sure you go with a new refrigerant if you going to replace an old unit.
  • by QuantumRiff (120817) on Friday October 12, 2007 @12:16PM (#20955493)
    By these guys [] back in 2000. The potato powered web server.. We could help our farmers, and power our data centers with beuwolf clusters of potatoes!
  • Reason To Buy A CPU (Score:2, Interesting)

    by bostons1337 (1025584)
    Just curious what you guys think about how this relates to buying a CPU. Do you think individuals and companies are going to take a big look at the CPU Energy Use when deciding on buying CPUs? I personally don't think it will become a deciding factor, like processor speed or L1 and L2 cache size, but I think it definetly helps in making a decision.
    • Re: (Score:2, Informative)

      by foobsr (693224)
      "The plan includes new products and services for IBM and its clients to sharply reduce data center energy consumption, transforming the world's business and public technology infrastructures into "green" data centers.

      The savings are substantial -- for an average 25,000 square foot data center, clients should be able to achieve 42 percent energy savings. Based on the energy mix in the US, this savings equates to 7,439 tons of carbon emissions saved per year." []
    • by Cecil (37810)
      Absolutely it's important. I bought an Athlon64 4400+ EE instead of an Athlon64 4400+ because the energy efficiency means it's energy efficient (obviously), low heat (less obviously) and therefore my system is much quieter (even less obviously), and uses even less energy to run fans. Energy efficiency has a lot of benefits for a computer. Once people start realizing this and trying it, they will see the light. There's absolutely no reason for your computer to sound like a jet engine (or, as the fans wear ou
      • by bmajik (96670) <> on Friday October 12, 2007 @01:06PM (#20956453) Homepage Journal
        My newegg order just showed up last nite. I wanted a machine that was as silent as possible, so I got an AMD BE2350 (the 45W TDP dual core Athlon @ 2.1ghz), an MSI k9 platinum (heatpipe cooling for the chipset), and a Gigabyte "silent-pipe" 8600 GT card.

        For a power supply i got a seasonic 330w S12 (variable speed ballbearing fan).

        My computer is entirely fanless except for the stock AMD CPU fan and the Seasonic power supply fan. There's not even a case fan. System and CPU temps seem to be stable around 40C.

        My vista "index" is 5.0, with the 5.0 being the lowest number and coming from the CPU.

        I wanted a really quiet machine. That meant eliminating fans. That meant buying energy efficient parts (the CPU and the Seasonic PS are both spendier than equivalent parts that don't stick to a tighter energy budget). But the machine _is_ quiet. I've got a kill-a-watt at home that I haven't tried out yet but I hope to see less than 100w of consumption. My old socket 754 machine is 5w sleep, ~100w booted but idle.

        I'm also going to be consolidating my "always-on" applications (file serving, possibly BT) onto a Windows home server machine so that i can have my other boxes power-save as much as possible without any real service interruption. Having a few songs here, a few videos there, etc means that I can't keep the majority of machines sleeping the majority of the time (WOL is pretty spotty IMO.. if you configure WOL such that a machine "can" wake, it usually will stay awake from other network noise)

        One of the other things i bought with this order was a new UPS. Sticking to a smaller power budget has other interesting effects -- like you can get away with a smaller (and cheaper) UPS to get the same amount of uptime.

        • by Spoke (6112) on Friday October 12, 2007 @03:07PM (#20958377)
          One of the biggest power draws these days are graphics cards. Often, graphic cards will draw as much power as the rest of the system. It's typical for the cheapest graphics card to add 10 watts to the power draw of the system when idle, with 25-50+ being common for medium to high end cards. Unfortunately, current graphics cards don't do much in the way of reducing power draw when idle.

          If you don't do any serious gaming, sticking with the onboard graphics will often reduce power draw significantly. If your mobo doesn't have onboard graphics, picking an inexpensive fanless graphics card will draw the least power.

          If you were using onboard graphics, I would expect your system would idle around 55w (+-5w or so). Peak power draw would be less than 100w. With the GPU you're using, I'd guess that it adds add 10-20w at idle and another 50w at peak. It'd be interesting to see what the actual numbers are.

          Something people often forget is that a good PSU with active power correction will also significantly reduce the apparently load on a UPS (as well as the grid if you don't have a UPS), not to mention that PSUs with APC are normally significantly more efficient. For example, if your system draws 100w but your PSU has a power factor of .5, you are actually pushing twice as much current through the AC line as a system drawing 100w but a power factor of 1. This ends up doubling the load on your UPS if you have one.

          These days it's fairly easy to build a system which idles below 50w as long as you're informed. A bit more research will get you something in the 30-35w idle range if not lowre. I do wonder what you had in your old Socket 754 machine which caused it to idle at 100w. I suspect it had an inefficient PSU and a mid-high end graphics card or wasn't using Cool'n'Quiet. All recent AMD systems I've seen which support Cool'n'Quiet idle at 60w or less unless you have a power sucking GPU.
          • by tksh (816129)
            FWIW, I have a 754 with four hard drives and a fanless card. It idles just below 100W and at 28C. I also have a Mac mini that idles at 30W.
            • by Spoke (6112)
              Sounds about right. Each 7200rpm hard drive will add close to 10w during idle.

              WD recently launched some low power drives, but they don't spin at 7200rpm. Performance is quite good considering and power draw is about half of a comparable 7200rpm drive.
    • With 12 systems running 24x7 my power bill takes a pretty good hit. But every time I think about reducing it, it occurs to me that every watt consumed ends up as heat, and I heat 9 months of the year this far north, and since I heat with electric, its a wash. Cut computers, more baseboard heating, same btu's and same electric bill. If I could switch to more efficient heating system then CPU efficiency might matter, but right now I cant see how it helps. Instead all I care about is MIPS per BUCK (everything
    • by timeOday (582209)

      Do you think individuals and companies are going to take a big look at the CPU Energy Use when deciding on buying CPUs? I personally don't think it will become a deciding factor

      I'd say we've already turned that corner. Intel aborted the netburst architecture (P4) because there was no easy way to dissipate more than a couple hundred watts, in that way power became the limiting factor. I don't think we'll see desktops reverting to 10W processors, nor do I think a 10% difference in consumption between comp

  • How big a fraction? (Score:2, Interesting)

    by columbus (444812)
    This looks like a positive development.

    It seems that the computer industry on the whole has become more concerned with energy efficiency over the last few years. I'm glad to see it. As a discipline, computer science is always looking for ways to eke out more efficiency, whether it is at the algorithmic level or at the level of chip manufacture. It seems to be a be a natural fit to extend this thinking further into energy consumption as well.

    But I have to wonder, how much of a difference can we make? I t
    • by Seenhere (90736)
      The best estimate I've seen recently is reported here: []

      (Doesn't include energy for manufacture or decommission; just operation.)

      Result: Roughly 10% of total energy consumption is due to computation.
    • I seem to recall statistics (noted on Slashdot, where else...) that came out of the Department of Energy a week or so ago that the energy required to operate the internet, computing, and communications infrastructure in the US was something on the order of 10% of the total power output.

      Even if that's wrong by a factor of 2, it's still significant - especially as it's by far the fastest-growing segment of power consumption in this country (and, presumably, in most others).

    • by DamonHD (794830)
      More than a factor of four in my case (more than 20x by some narrow measures): []

      and []

      Basically I replaced my entire 670W rack of Web-facing servers at home with a single Linux laptop that uses ~18W off 12V DC (+7W wasted in the mains adaptor), which sometimes now runs off-grid on solar PV so that 12V DC power figure is meaningful.

      I have no reason to believe that my situation is really exceptional, and I'm running a fairl
  • I had concerns about power draw when setting up a new PC to replace my aging setup. I've already piled on a considerable amount of electronics in the small room I live in. Having both A/Cs activate on the same breaker causes the breaker to trip, so even the added burden of a computer upgrade was worrisome.

    Having the additional information would have taken off a good bit of stress, and would help a bit in calculating how much headroom I needed in the PSU to keep the PC itself running smoothly.
  • Tax benefit (Score:4, Interesting)

    by slackoon (997078) on Friday October 12, 2007 @12:27PM (#20955723)
    The government gives tax benefits for driving hybrid vehicles and I believe they should do it for energy efficient computers as well. "According to the Computer Industry Almanac Web site, at the end of the year 2000, there were 168.84 million computers in use. The projection for the end of 2001 is 182.24 million." So just imagine how many there are now! With that many computers, many of which are never turned off, the energy savings could be enormous.
    • Re:Tax benefit (Score:5, Insightful)

      by Yartrebo (690383) on Friday October 12, 2007 @01:09PM (#20956505)
      Not having a computer is better in terms of energy demand than even having a very efficient computer. Same for the hybrid car. For this reason I find these tax breaks perverse.

      Giving tax breaks for efficient items penalizes those who conserve the most by not even having the item or by using less. A business that invests money into writing more efficient software and using less servers should not be penalized vis-a-vis a business that invests the money into more efficient servers.
      • Not having a computer is better in terms of energy demand than even having a very efficient computer.
        You're saying that it is more energy efficient to have to drive to the bank than to do your banking online?

        Owning a computer is critical to functioning efficiently in modern society. Offering incentive NOT to own a computer is like offering incentive NOT to learn how to read and write; it's totally counterproductive.
        • by Yartrebo (690383)
          I was talking about computer servers, where many tradeoffs can be done between software and hardware. Giving up a home server (massive energy hog for the services rendered) is a lot easier than giving up a primary PC. Likewise, it is much easier for a company to improve its software and buy less servers than to make do with fewer PCs.

          PS: Probably the way with the least negative side effects to improve efficiency would be a blanket tax on all dirty, nonrenewable, or almost fully developed energy sources (in
          • by Zeality (921282)
            Hey, I couldn't find a PM option, so I'm hoping you get e-mail notification of comments to you, Yartrebo: I ran across an old post of yours at the Game Dev forums in which you spoke of ripping models via AdriPSX in 2002: [] The post's links are dead (not surprising since it's 5 years old). At the Chrono Compendium, a bunch of us are obsessively pulling out all the stops to map Cross's file structure and rip its assets, but the community isn't
      • by slittle (4150)
        People who "conserve" by not buying things are not contributing to the economy, tax revenue or technological progress, so why the hell should they get tax breaks?

        Expensive toys fund the economy, the government and advance the state of the art so that everyone can enjoy a better life while using less resources. Your theory on conservation is simply useless (at best).
        • by gedhrel (241953)
          I don't quite understand your jump from economic growth to a better life for everyone. The poverty gap increases; everyone (for the proper meaning of the word) clearly aren't all having a better life; and economic growth is a poor straw man used by politicians, compared to measures of actual welfare.
          • by slittle (4150)
            Well, I don't live in the USA so perhaps I take the lack of corporatist corruption for granted...

            True, economic growth doesn't necessarily make life better for everyone, but it at least makes it possible. Stagnating doesn't do society or the environment any good.
  • Performance? (Score:3, Insightful)

    by Speare (84249) on Friday October 12, 2007 @12:47PM (#20956063) Homepage Journal

    Okay, just stating the wattage is like stating MPG for a car or the energy usage for a fridge. But every year, car performance stays about the same or gets worse, and the fridge ain't getting more full. There doesn't seem to be a single useful energy metric that can drive informed purchasing decisions.

    So how do you deal with CPUs that are twice as powerful in the next product cycle? The wattage will be about the same, but the amount you can get done with that chip will be much higher. It's like next year's car suddenly weighs twice as much, or goes twice as fast, or seats two whole families, while getting the same mileage. You can't even consider it in two tiers like "passenger cars vs truck frames" because you have to deal with 2008, 2009, 2010, 2011 performance tiers... they change all the time. How can someone make an informed decision from this?

    • Re: (Score:3, Insightful)

      by DMUTPeregrine (612791)
      Watts per MFLOP. Or MIPS. Or Watts per Point, where point is an average on some benchmarking system. Just giving watts for a computer is like just giving gallons for a car. You don't know how many miles it can go on those gallons, and so the figure is useless.
    • by Uerige (206572)

      For a typical desktop system? Try getting the lowest absolute power x86 compatible cpu (speed doesn't matter). It certainly won't idle any slower than any other one, but it might do it more silently. These kind of metrics aren't meant to be interpreted by anyone and their mom.

      Now if you're building a datacenter or, possibly a gaming rack, take a look at all of the processors that are actually fast enough for your demands and then pick the one that uses the least power under your actual expected load.

  • by Anonymous Coward
    *Real* programmers eat microwave popcorn. However, they use the heat from the CPU to cook it instead of using an actual microwave. *REALLY* good programmers can even tell which process is running by the rate of popping.
    • Maybe you're referring the the programmers which throw poop and are just as likely to write a shakespeare as they are to write a decent program.

      thats right. codemonkeys.
  • We colo AppleTVs. Why? 1Ghz Core Solo, 18W. We also do Mac Minis. Why? 2x2Ghz Core 2 Duo, 40W. Let's put 125 Mac Minis, up against the IBM mainframe and see who's faster. []
  • by oyenstikker (536040) <slashdot.sbyrne@org> on Friday October 12, 2007 @01:23PM (#20956751) Homepage Journal
    How about "burning library of congresses"
  • These benchmarks are interesting, but are they relevant to real life? There are too many factors to say.

    Consider a 20 watt CPU which sits idle 99% of the time. Then imagine a 40 watt CPU which is loaded to 100% all the time. Which is "worse?" I'd say the 20 watt CPU is worse, because it's 20 watts of completely USELESS power.

    Or imagine that a corporation has a cash-cow application. They can make $10 million per year if they run it on server X which draws 2000 watts. Or, they could make $5 million if the

  • We were 450 people working at my previous job. More than 400 used computers. The elevators of that building used more than 10 times the current of the computers.
  • Depends entirely on what the processors are doing, just as the equivalent metrics for cars depend on the weight and speed of the car. What I'd like to see is a rating of the load that, for example, an operating system puts on the CPU. Let's say that you want to compare Vista vs Mac OSX or some brand of Linux OS, doing some basic activities (starting up, copying data, etc), and give the results in a way that translates into carbon units.
  • my Athlon Xp mobile 1800+, run at 1,5 GHZ. But if I do "powercfg.exe /change profile /processor-throttle-ac CONSTANT" with winxp, it run at 654MHz. It's enough for old games for example.

Work is the crab grass in the lawn of life. -- Schulz