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Lies, Damn Lies, and Battery-Life Statistics

theodp writes "What if automakers measured gas mileage by rolling their cars downhill with their engines idling? They might, Newsweek's Daniel Lyons suggests, if they took inspiration from the MobileMark 2007 notebook battery-life benchmark test, the creation of a consortium called BAPCo, whose members are — surprise — computer makers and other tech companies. Laptops score big numbers, Lyons explains, because they're tested with screens dimmed to 20%-30% of full brightness, Wi-Fi turned off, and the main processor chip running at 7.5% of capacity. Professional reviewers see company-generated battery-life claims as a joke. 'The rule of thumb is that in real-world use you get about 50 percent of rated battery life,' says a Gizmodo associate editor. Leading the call for reform is the not-necessarily-altruistic AMD, who gripes that MM07 was created in Intel's labs and rigged so Intel chips would outscore AMD chips, which draw more power when idle."

5 of 200 comments (clear)

  1. Apple Don't by Space+cowboy · · Score: 5, Interesting

    Take a look at Anandtech's MBP review. The tagline 'Battery life to die for' sort of gives away the tale though.

    Apple claim 5-8 hours. Anand got 4.92 (heavy downloading + XVid + Web browsing) to 8.13 hours (Wireless web browsing) with the screen at half-brightness ("completely useable") and no funny optimisations.

    Maybe, just maybe, there's something to this "our batteries are better" thing they've got going; if someone comes out with a spare-battery-attached-to-a-magsafe-connector for those die-hards who absolutely *need* it, angels may sing in the treetops. Personally I've never needed to change the battery in my portable (whatever portable I've had) so it's no big deal to me. Yadda yadda, one datapoint not a trend...

    Simon.

    --
    Physicists get Hadrons!
  2. Hate to sound like a Mac whore by twistedcubic · · Score: 4, Interesting

    but I get five hours of battery life on a Macbook (last year's model), so I think Apple doesn't lie about its stats (because they don't have to?). Despite all the claims that Macs are overpriced, I think these are among the cheapest non-netbooks you can get with great battery life. IMO, laptops which last only 2.5 hours on a battery should not be sold.

  3. Re:Does anyone pay attention to battery life anymo by Anonymous Coward · · Score: 4, Interesting

    2.5 hours? Really? What's the point? My two and a half year old Thinkpad T60 gets 5 hours on a bad day. My friend with a similarly spec'd Thinkpad (a bit older) claims to have gotten 9 hours with wifi off and more like 7 hours in reasonable usage (his is tweaked a bit better). Both of us have just the extended battery (there is also space for a second, smaller battery instead of an optical drive).

  4. I don't trust Apple's sealed-in batteries by argent · · Score: 5, Interesting

    I will never buy a laptop with a non-removable battery even if it gets 8 hours playing MMOs at full resolution. I *have* a Macbook Pro, and if it had an "iBattery" my laptop would have been destroyed when the battery failed and swelled... instead of having the battery pop safely out of its compartment.

    Better battery, great, but I'll take a laptop that's a millimeter thicker if that's what it takes to put a door on the battery compartment.

  5. Standards by fermion · · Score: 4, Interesting
    As long as everyone is using the same standard, it is not that big of a problem. If we go before cars, to horses, we can see why this is. The story is that James Watt used the term horsepower to market the steam engine, for instance, the ROI might be related to the number of horses you did not have to maintain. The story also is that he did not make his horses work very hard. As today, the ROI was well overstated, but as the relationship became less about horse and more about steam engines, the standard became more useful.

    We saw the same issue with clock cycles. People misinterpreted, and the marketing drones were more than happy to let them do so, clocking as measure of work. A faster processor did not mean that more work would get done, but the consumer did not know that, so they would pay more for fantasy benefits.

    In terms of fuel consumption, and battery life, the reality is more of the horsepower that the gigahertz. As long as one is running comparable tests, then one can assume that a car rated at 20 mpg will run longer than a car rated at 10 mpg, just like a computer that is rated for 4 hours will run longer than a computer rated at 2 hours. The problem, like the horse, is related the terms horse, hour, and mpg to actual physical quantities. We know that the physical performance is actual 20% or so less in real life.

    As mentioned elsewhere, what messes life up is companies like Apple that advertise 3 hours of battery life, and, under normal use, actually get it.

    --
    "She's a scientist and a lesbian. She's not going to let it slide." Orphan Black