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Portables Power Hardware

Lies, Damn Lies, and Battery-Life Statistics 200

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."
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Lies, Damn Lies, and Battery-Life Statistics

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  • Apple Don't (Score:5, Interesting)

    by Space cowboy ( 13680 ) * on Saturday June 20, 2009 @02:53PM (#28403507) Journal
    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...

  • by Hadlock ( 143607 ) on Saturday June 20, 2009 @02:53PM (#28403517) Homepage Journal

    Most people expect 2.5 hours of "good use" out of a laptop battery when new. This number hasn't really changed since 1998 or so. I can't remember the last time I used battery life when evaluating a laptop - if you NEED more than 2.5 hours of battery life, you just buy a second battery. People assume half the life stated as rule of thumb the same way I assume real world gas mileage as (EPA gas mileage * 0.8) for cars I drive.
    The correct title for this article is "Does anyone still pay attention to marketing hype about batteries, or, how I learned to stop caring and ignore the marketing hype".

  • by twistedcubic ( 577194 ) on Saturday June 20, 2009 @02:56PM (#28403529)
    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.
  • by marc.andrysco ( 1173073 ) on Saturday June 20, 2009 @03:00PM (#28403575) Homepage
    My latest laptop advertised 2.5 hours of battery life, which I would've been fine with. It's enough to last through two classes, after which I can normally find a power outlet.

    I wasn't very careful looking at the battery life, and, to my dismay, I took it home to find out it could only hold a charge for 1.5 hours. This is even on pretty conservative settings with the screen dimmed as low as possible. Now that it's starting to age, I'm down to about 1 hour of battery, which doesn't even last through my 75 minute classes.

    Most people expect 2.5 hours of "good use" out of a laptop battery when new. This number hasn't really changed since 1998 or so. I can't remember the last time I used battery life when evaluating a laptop - if you NEED more than 2.5 hours of battery life, you just buy a second battery.

    Oh, how I wish that were the case.

  • by Anonymous Coward on Saturday June 20, 2009 @03:06PM (#28403613)
    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).
  • by slaker ( 53818 ) on Saturday June 20, 2009 @03:15PM (#28403665)

    I get seven to eight hours of normal use on a 14" T61 with the nine cell primary and the ultrabay battery, using an Intel SSD. I really CAN run my system all day off batteries, if I need to, but given the number of cells I'm using, that's something I really expect to be able to do.

  • 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.

  • Standards (Score:5, Interesting)

    by fermion ( 181285 ) on Saturday June 20, 2009 @03:26PM (#28403727) Homepage Journal
    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.

  • Three Numbers (Score:4, Interesting)

    by Octorian ( 14086 ) on Saturday June 20, 2009 @03:33PM (#28403765) Homepage

    In my own experience, I've found there are 3 different battery life numbers you run into with any laptops. These numbers are always significantly different.

    1. The life the manufacturer tells you that you'll get
    2. The life every reviewer (and some /. readers) swear you'll actually get
    3. The life you actually do get

    Regardless of 1 or 2, I've found that 2.5 hrs is a good ballpark for 3 when the laptop is new. (ok, for Apple, the newest one I've used is a bit over 2 years old, but was in that ballpark when new. My newer HP w/o the add-on battery is a little better than that, but same ballpark)

  • Re:Apple Don't (Score:3, Interesting)

    by Ihmhi ( 1206036 ) <> on Saturday June 20, 2009 @04:07PM (#28403939)

    What baffles me is how battery technology hasn't improved a whole bunch. I know there's no like, O'Vac's Law or something like Moore's Law, but why has it proven so difficult to improve battery life for laptops beyond 4-5 hours?

  • I would surmise that this has to do with the fact that Thinkpads seemed to be geared more towards the businessman - there would be hell and a half to pay if your laptop couldn't last for a flight on a plane. Their customers needed long battery life and they got it.

    A lot of my friends who have laptops rarely actually have them untethered - they can take them around conveniently, but they always plug it into whatever open socket happens to be nearby.

  • by Macman408 ( 1308925 ) on Saturday June 20, 2009 @04:13PM (#28403985)

    Apple, like many companies, is often rather fearful of power adapter and battery issues. If you have a power adapter that's sparking, or a battery that's bulging, or something that might pose a safety risk, they'll often choose to replace it for you (in warranty or not) rather than let you continue using it, risk getting hurt, and starting a lawsuit (or a recall).

    Obviously, this varies a lot. A fraying power adapter cord is also likely to be caused abuse, and they'll figure that you're smart enough that if it's sparking, you probably shouldn't use it while sitting in a pool of gasoline (or at all, for that matter). And even a bulging battery might be called a consumable, and they'll just tell you to buy a new one. It depends on a lot of things - if you have/had AppleCare, the mood of whoever you're talking to, how much money you regularly throw at Apple for new products, how widespread the problem is, how many times you ask, etc.

  • Re:Apple Doesn't (Score:3, Interesting)

    by crmarvin42 ( 652893 ) on Saturday June 20, 2009 @04:30PM (#28404107)
    Exactly! I bought a new battery for my old powerbook about 4 years after I got it and the replacement batter had so much more juice that I actually got 2x the battery life out of it that the original battery gave me (when brand new).

    The problem isn't that batteries aren't improving, but that battery improvements aren't keeping pace with hardware requirements. The recent shift toward performance/watt and Apple's larger, but not exteranlly accessable battery seem to be aimed at addressing this imbalance.
  • Re:Apple Don't (Score:2, Interesting)

    by slaker ( 53818 ) on Saturday June 20, 2009 @05:14PM (#28404363)

    Apple notebooks are manufactured by Asus. Don't you think that if there were some kind of significant gain in technology for battey life that it would show up in other Asus-manufactured products?

    Here's another idea: Apple lies about battery life just like everyone else.

    Really, now, which idea is more likely?

  • Weight (Score:2, Interesting)

    by zogger ( 617870 ) on Saturday June 20, 2009 @05:26PM (#28404453) Homepage Journal

    The number one selling feature for new laptops seems to be weight (and slimness). If "consumers" would be willing to carry the same weight they did some years ago, sure, you could have batteries that would last a long time, even with more modern processors and so on. but they don't, lightweight sells, and people believe the marketing crap about battery life, so there ya go.

      An extra pound or two of battery would do wonders, but they can't hide that extra pound or two in the specs, while they can fudge about battery longevity.

      Batteries have gotten better, from sealed lead acid to NiMH to LiIon in laptops, but still, if they keep reducing size and weight, your amp hours of storage will never get much better. You can maybe maintain parity, but it won't get better.

    I think there would be a market for it, but obviously no laptop manufacturer wants to take a chance on that, they all seem to be on the lighter is always better schtick.(same with cellphones, lighter and teeny tinier) Personally, I think laptops got "light enough to not suck" several years ago, but obviously most people just don't want to carry anything heavy anymore like they did even five years ago. Example, you can get pretty decent notebooks now at around 3 lbs. Add 2 lbs of extra battery, still at five pounds, what was considered really lightweight not that long ago. You'd have pretty good all day long battery then..but would they sell?

  • What OS are you running? Even though I am primarily a Windows guy (Quite happy with XP x64) I've found that the ultra small Linux distros can squeeze more life out of a battery. I would try DSL, DSL-N, or Puppy, going from least juice to most.

    I have had customers bring in laptops in the same predicament and after telling them how much a new battery would cost (and hoping they don't have a coronary) I show them DSL and Puppy and tell them that running one of these instead of Windows could extend their battery life. Depending on the model some have doubled the amount of time they get and they are all quite happy. After all, it is a laptop. you are using it to take notes and read emails, not run Bioshock.

    So give them a try. There are plenty of Puplets you can choose from if you need something customized, but for best battery life I would try DSL and DSL-N first. IIRC DSL-N has Abiword included which is fine for note taking in class. Both DSL and Puppy have easy to use instructions for putting them on a USB stick if you are talking about a Netbook or for whatever reason can't use a CD. All it will take is a couple of hours of your time, a few blank CDs and a few hundred MB of bandwidth to give it a go. And if you are down to an hour of time left on a full charge, what have you got to lose?

  • Re:Already have that (Score:3, Interesting)

    by hudsucker ( 676767 ) on Saturday June 20, 2009 @06:03PM (#28404719)

    Running off the external battery shouldn't attempt to charge the internal battery.

    Consider running off of 15v aircraft adapters, which provide enough power to run the computer, but not enough to charge the battery.

    Apple doesn't publish how the current MagSafe adapters are designed, but they do have a document [] that explains how power adapter sensing worked on the PowerBook. The power plug shell is used an "adapter sense" line to signal the adapter type to the computer's power management unit.

  • by jaclu ( 66513 ) on Saturday June 20, 2009 @06:10PM (#28404765)

    Just a guess, but since they typically dont run an antivirus app in the background, both cpu and disk can idle more.

    Not trying to be a macista, but I can only note that I still get around 4h wifi surfing at medium brightness out of my two year old macbook, so apple definitely do give reasonably honest battery estimates.

  • Re:Apple Don't (Score:3, Interesting)

    by BikeHelmet ( 1437881 ) on Saturday June 20, 2009 @06:47PM (#28405071) Journal

    Why can't laptop vendors be more like these guys []?

    Their little device is sold as "around 10+ hours", which turns into 15-16 for music, 10-11 for web browsing, and about 8-9 for emulators.

    But then again, their device is so small that they had to take preorders to pay for it. Lying about that stuff would seal their doom, while with a huge company more sales(even based on false specs) appease the investors.

  • by cibyr ( 898667 ) on Saturday June 20, 2009 @07:43PM (#28405647) Journal

    Microsoft still needs to pull their finger out. OS X gets 20-25% longer battery life on the same hardware as Windows Vista or 7: []

  • by WaltFrench ( 165051 ) on Sunday June 21, 2009 @01:28AM (#28408031)
    When I showed the Genius my swelled battery, he didn't even want to know the purchase date, etc. He just headed back to the store room for a replacement. Some companies pretty much *have to* do The Right Thing, as another post implies. Culture or Holier than thou advertising, I don't care.
  • by Hadlock ( 143607 ) on Sunday June 21, 2009 @02:55AM (#28408477) Homepage Journal

    Truth in advertising laws were designed to protect gullible babyboomers who did not grow up with advertising from a young age. Consumers these days are so jaded by marketing and advertising they just ignore it for the most part, or at least do research on the products they buy before plunking down $100+.

  • Re:Apple Don't (Score:2, Interesting)

    by Khyber ( 864651 ) <> on Sunday June 21, 2009 @02:04PM (#28412147) Homepage Journal

    "Really, now, which is more likely: everyone's lying from reporters to users and in some huge conspiracy, or Apple's batteries really meet the stated specs?"

    I'll bet on them all lying because they're too busy going 'oooh shiny!' to pay attention to the real details.

    When I do battery life testing, I run everything full throttle. That's a true performance indicator. I turn off all power-saving nonsense in software and hardware as much as I'm possibly allowed to, crank everything from volume to screen brightness to the maximum (I even have a little program that lets me modify the transmitting power of the WiFi and I crank that from 71mW to 251mW,) and then I run a video game.

    In my comparison of Toshiba, Apple, and HP laptops, not a single one of them actually lives up to the advertised battery life, though they all vary. Playing Fallout 3, HP got about 30% of a two hour advertised battery life. Apple (under Boot Camp) got about 40% of an advertised 3 hour battery life (older MBP) and the Toshiba got about 30% of an advertised 3 hour battery life. Apple certainly won but I really wouldn't call it a victory to be proud of.

The human mind ordinarily operates at only ten percent of its capacity -- the rest is overhead for the operating system.