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Portables Power Hardware

Lies, Damn Lies, and Battery-Life Statistics 200

Posted by kdawson
from the guilty-as-charged dept.
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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  • by FishWithAHammer (957772) on Saturday June 20, 2009 @03:00PM (#28403577)

    Hasn't changed? The hell it hasn't. My new Dell Studio 15, with the standard battery (6-cell, I think), gets three hours and forty-five minutes under regular usage (i.e., not playing Dwarf Fortress or doing something graphically intensive). It'd get more with Aero Glass off.

  • Lenovo here (Score:3, Informative)

    by SchizoStatic (1413201) on Saturday June 20, 2009 @03:01PM (#28403585) Homepage Journal
    I have a cheap lenovo from last year and if I am on 50% brightness with wifi on and just browsing web with some videos I can go 3 hours. The battery is rated for 3. *shrug*
  • Re:Apple Don't (Score:5, Informative)

    by wnknisely (51017) <`moc.liamg' `ta' `ylesinknw'> on Saturday June 20, 2009 @03:12PM (#28403647) Homepage Journal
    For what it's worth, I'm seeing numbers comparable to these on my new Macbook pro. Perhaps Apple is using a different benchmark than the one in the article above?
  • by OrangeTide (124937) on Saturday June 20, 2009 @03:14PM (#28403657) Homepage Journal

    I got my Macbook because it makes a pretty decent Linux box (although I now dual-boot OSX because Apple has slowly wormed its way into my life), and the lowest end Macbook is pretty affordable. Comparable in price and specs to a mid-range laptop. And yes it does get good battery life (the battery life is better in OSX than in Linux though)

    If you use computers the way I do, the you can really get those 4 hours that those cheap PC laptops claim. I use it in the dark(so screen dimmed), no WiFi, command-line only running a text editor for Vi. Occasionally kicking on the CPU to compile a .c to a .o and link the .o's (using 'make' saves a tremendous amount of battery life). My Macbook got a little over 5.5 hours for me on a flight before it had to shut down(just writing code and reading man pages). If I would have sprung for the Macbook Pro it would have been more like 7-8 hours though.

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

    by LynnwoodRooster (966895) on Saturday June 20, 2009 @03:17PM (#28403675) Journal
    I get 4-4.5 hours out of my 4 year old Dell D505. I leave the backlight at 50% - it's too bright otherwise. WiFi usually on, new battery from 1.5 years ago. Seems to last about what Dell claimed! Now, if I'm doing non-stop compiling or heavy-duty FEA then the battery life drops WAY down. But then I'm usually seated at a desk, where an outlet is just a few feet away. When I'm traveling and need the battery life, it's typically just web and e-mail and it lasts plenty long for that...
  • Already have that (Score:5, Informative)

    by SuperKendall (25149) on Saturday June 20, 2009 @03:20PM (#28403687)

    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

    This is exactly why I don't understand the fuss over non-removable batteries. You get better battery life, and if you need extra power you've always been able to buy external battery packs [batterygeek.net]. They have cable that attach to the Magsafe connector. You can get them in a range of sizes, including sizes that are not much larger than a spare battery would have been anyway...

    Similarly there are tons of external packs for smaller devices like the iPhone/iPod (or anything usb charged).

    I also have not often found the need for an second battery in a laptop if I can get at least three to four hours out of it. Basically the only time is an international flight, and for that the external batteries are perfect. Heck, until it broke the Solio [solio.com] solar powered recharger I had could even recharge itself in-flight as long as I was at a window!!

  • by SuperKendall (25149) on Saturday June 20, 2009 @03:25PM (#28403721)

    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.

    But perhaps the battery would not have swelled had it been designed into the computer instead of being an Apple re-branded battery manufactured by someone else.

    Perhaps Apple's move to all sealed batteries is because they got tired of the weakest link in the chain being overly cheap manufacturing processes from other companies bringing their own equipment down...

    If for some reason the Apple laptop battery did swell and cause the system to fail, I'm not sure what the issue would be - you'd get a new laptop.

  • by quanticle (843097) on Saturday June 20, 2009 @03:43PM (#28403815) Homepage

    If for some reason the Apple laptop battery did swell and cause the system to fail, I'm not sure what the issue would be - you'd get a new laptop.

    Well, assuming the laptop was still under warranty, of course. If the laptop wasn't under warranty he'd have had to pay for a brand new laptop, rather than simply purchasing a replacement battery from eBay or something.

  • by quanticle (843097) on Saturday June 20, 2009 @03:54PM (#28403879) Homepage

    I suppose it depends on what you consider to be "good use". I personally get at least 4.5 hours of use out of my Toshiba A305 while coding and web browsing. Good thing, too, since I'm often not able to find a free power outlet while I'm at school.

  • Re:Apple Don't (Score:5, Informative)

    by speculatrix (678524) on Saturday June 20, 2009 @05:12PM (#28404349)
    there's no point in ordering a *spare* battery when you buy a laptop; ordering a *second* battery because you're travelling a lot might make sense. this is because LiIon batteries age, and you can only slow down the ageing by keeping them 40% charged in a moderately cool place.

    LiIon batteries also lose capacity after a number of charge/discharge cycles, the number varies according to how deep the cycles are and the temperatures you reach in the process. When the battery packs are particularly expensive - think Prius and other electric cars - the battery management electronics are crucial to protecting the investment, and the batteries are never run anywhere near flat and particularly are never fully charge to prevent some cells overcharging, and the charge/discharge controlled carefully to prevent temperature rises leading to premature ageing.

    thus, in conclusion, keep your laptop battery cool, don't thrash its battery, don't deep cycle it, buy a good brand so you can buy a new battery *in*the*future*not*for*storage*.
  • Re:Apple Don't (Score:3, Informative)

    by arminw (717974) on Saturday June 20, 2009 @05:50PM (#28404615)

    ...Apple lies about battery life just like everyone else...

    I get about three and a half hours of battery life on my Macbook pro surfing the web with wireless turned on. Manufacturing a product and producing an integrated hardware and software design are two entirely different things. Asus along with all the other manufacturers of machines that get Windows installed on them, make only half of the computer and cannot possibly integrate the software including power management the way Apple does. It is the design, not the manufacturing that makes the difference.

  • Why bother installing just to check it out? I'm sure that you have an old spare flash lying around, yes? Both DSL and Puppy have flash installers. Just boot off the CD, run the flash installer, answer a couple of questions, and there you go. The nice thing about running off the flash is if you have more than 128Mb of RAM you can simply have the entire OS loaded into RAM with the TORAM option flag. That way you don't even need that battery sucking HDD unless you need the extra space.

    I had a customer whose GF managed to drop his laptop and break the HDD cage. It wasn't cheap to replace that, let me tell you. I told him about running DSL on a flash and he tried it. He liked it so much he went and got a PCMCIA flash adapter so the flash card wouldn't stick out and now just runs DSL-N on it. it gets better battery life than before with XP according to him, and by having the entire OS loaded into RAM it is very fast to respond. So why not give it a whirl on flash? I have ran DSL on 256Mb, but I would recommend 512Mb or 1Gb so you have plenty of space for programs and files. The entire install of DSL with Abiword was something like 96Mb which left plenty on my 512Mb for my files.

    All it takes is a couple of hours to play with it and an old flash drive. If it turns out it works well for you then you can swing by Newegg or surpluscomputers.com and pick up a cheap flash adapter for your laptop and an 8Gb card and can unplug your HDD and save even more juice. That way even if you pick up another laptop or Netbook you will have a nice SSD based secondary for a backup.

  • by Anonymous Coward on Saturday June 20, 2009 @10:13PM (#28406819)

    You don't seriously expect that the internal battery is any more "apple manufactured" than the removable battery was, do you?

    It is, actually. The old, swappable batteries used conventional cylindrical lithium ion cells, whereas the new, not-swappable-but-still-replaceable-if-you-have-the-right-screwdriver battery is a lithium polymer with stacked rectangular cells. Apple owns numerous research and manufacturing patents related to the latter. Apple does not manufacture them in-house, of course, but they do design and test them.

  • Re:Bad analogy (Score:3, Informative)

    by neBelcnU (663059) on Saturday June 20, 2009 @10:31PM (#28406929) Journal

    WRONG.
    No matter whether closed-loop or open-loop, modern FI always injects the amount of gas most closely matching the volume of air taken in.

    Closed-loop (using the oxygen sensor in the exhaust) is totally adaptive, if there's unused O2, add more fuel. Open-loop (no O2 sensor, or 02 sensor not hot enough or not working or...) thet FI computer consults a table based on all the usual factors: Mass-air flow, engine temp, throttle position.

    In either case, the opinion that your FI turns off the flow of fuel when you let off the gas is wrong. While the FI can indeed cut the fuel, it does so only under extremely rare conditions. I've actually never been able to make it happen on my car.

    Oh, and the reasons? When you shut the fuel off, you run the risk of a lean mixture, which is both damaging to the engine (burning holes thu pistons) and super hi rush of NOx. That's why your throttle plate doesn't snap fully to the idle position, that slight loiter is to allow the system to "balance out" before returning to idle.

    Damn, wasted my mod points to write this.

  • by OrangeTide (124937) on Saturday June 20, 2009 @10:42PM (#28407009) Homepage Journal

    Since I presume that you really mean "VIM", then I have an information which might be interesting to you.

    No, I use nvi.

    Also writes to .swp on Vim have an impact if the file is opened O_SYNC, else it goes to cache and is rarely written. I just installed and tried Vim and the harddrive indeed does stop (I can hear it). Linux will indeed eventually wake up and commit the cache to disk. But it does take a while, but it's totally tunable. Takes about 7 minutes(and 13 seconds) for a 16K text file on my system to be committed to disk after it has been "written" 8 times (timed with stop watch, nothing super accurate)

    strace output shows that I am correct (opens swp file with O_RDWR|O_CREAT|O_EXCL|O_LARGEFILE). as well as checking the source in http://vim.cvs.sourceforge.net/viewvc/vim/vim7/src/ [sourceforge.net]

    In other words, your conjecture is wrong.

  • Re:Apple Don't (Score:5, Informative)

    by moosesocks (264553) on Sunday June 21, 2009 @02:41AM (#28408425) Homepage

    All of these things are true for Lithium Ion batteries.

    However, Apple's current line of notebooks use Lithium Polymer instead of Lithium Ion. Additionally, the charging circuitry is supposedly much more sophisticated.

    I'm not sure if the modes of failure for commerical Li-Pol packs are well-known at this point, and I have no reason to believe that they'd be the same as those for Li-Ion.

  • Re:Apple Don't (Score:1, Informative)

    by Anonymous Coward on Sunday June 21, 2009 @09:56AM (#28410311)

    How come other Asus made laptops are not made of CNC machined aluminium?
    How come other Asus made laptops are do not come with mag safe style power connectors?
    How come other Asus made laptops do not have multi touch trackpads?
    How come other Asus made laptops do not come with OS X installed?

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