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."
Who did this study? (Score:5, Funny)
Captain Obvious?
Re: (Score:3, Funny)
Enough said.
gas mialage (Score:5, Funny)
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Let's start with a mole hill and work our way from there.
Apple Don't (Score:5, Interesting)
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.
Re:Apple Don't (Score:5, Informative)
Re:Apple Don't (Score:5, Insightful)
...Perhaps Apple is using a different benchmark...
Perhaps Apple computers are able to manage power better because Apple is the only computer maker that engineers their hardware and software together and is thus able to optimize battery life.
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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?
Re:Apple Don't (Score:4, Insightful)
Asustek assembles the laptops, but certainly doesn't manufacture or supply the batteries. If you know who supplies those batteries, their controllers, or the controller software please share (and cite). I certainly couldn't find that information.
Here's another idea: Anandtech and the others who have tested the batteries and verified Apple's numbers don't have any reason to lie.
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?
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...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 desi
Re:Apple Don't (Score:5, Informative)
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*.
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Also, remove the battery (and keep it around 40%, with a full cycle once a month) if you are running mostly on AC.
Re:Apple Don't (Score:5, Informative)
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.
I don't trust Apple's sealed-in batteries (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.
Apple doesn't trust other batteries (Score:3, Informative)
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
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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.
Re:Apple doesn't trust other batteries (Score:4, Interesting)
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.
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Speaking of additional factors to throw into the mix:
While there's something to be said for knowing the exact hardware that your software will be running on, most reviews will comment on the very well-designed power management in Windows. In fact this is something that, from what I understand, is continually being patched through windows update. So there's a good chance that the laptop you bought 2 years ago, with the same version of windows, has a *longer* battery life, on average, than when you originally
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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: http://anandtech.com/mac/showdoc.aspx?i=3582 [anandtech.com]
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Re:Apple doesn't trust other batteries (Score:5, Insightful)
Apple, like pretty much all the domestic PC brands, has little to no manufacturing capacity in-house. Possibly some prototyping, and likely some customization/assembly; but all the serious manufacturing is handled by a bunch of OEMs and their suppliers. The cells will be sourced from some third party in any case.
Re:Apple doesn't trust other batteries (Score:5, Insightful)
How appropriate, then, that the one thing they *do* oversee in-house is the manufacturing processes for the *cases*. They've invested quite a bit in manufacturing process development and patenting, resulting in things like the "Unibody" laptops and those highly-resilient aluminum coating materials.
So many of their customers, after all, "judge a notebook by its cover"...
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Except that the battery is *not* non removable. The battery is removable in the same way as your hard disk or your memory are -- you wouldn't do it every day, or even every week, but if you need to replace it, you can.
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Already have that (Score:5, Informative)
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!!
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If you are particularly concerned, the way to go would be to drain the external battery first, by running your fully charged laptop off of it, until the external pack was empty, and then run off the internal battery, charging both when you get to power. In practice,
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Actually, I have a control on my Dell laptop to prevent exactly this, where it will not charge the internal battery. It can also be used when you don't want to charge the battery because you won't use it for the enxt few days..
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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 [apple.com] 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.
Actually does not charge internal battery (Score:2)
Wouldn't this manner of external battery be incredibly wasteful? Assuming the laptop does not have a way of detecting that it is an external battery and not a power adapter, then I would assume it would attempt to re-charge the internal battery.
For whatever reason, external battery packs for the Macbook/Macbook Pro (basically anything with MagSafe) only power the laptop, they do not charge the battery (even if empty). You can read the notes about that on the site I linked to, they spell that out pretty cle
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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.
You mean like this [quickertek.com], this [batterygeek.net], or this [hyperdrive.com]?
No endorsements from me here, mind you - just wanted to point out that there are indeed such products for sale. I, however, neither own a MacBook nor have ever had any desire for a second battery on my PowerBook.
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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?
Re:Apple Doesn't (Score:3, Insightful)
Battery tech has improved, but the computer manufacturers use that extra ability to run more stuff. It's just like how computers don't seem to work any faster than they did ten years ago--advances in memory and processor power get eaten up by bloated software and additional "features". And 4-5 hours seems to be what most people consider acceptable; few are willing to trade off power, screen size/brightness, features, etc. for longer built-in battery life.
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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.
Weight (Score:2, Interesting)
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 fudg
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Why can't laptop vendors be more like these guys [openpandora.org]?
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.
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Your heat from the laptop killed the battery. You should have taken it out when you didn't use it and left it plugged in.
Does anyone pay attention to battery life anymore? (Score:4, Interesting)
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".
Re:Does anyone pay attention to battery life anymo (Score:5, Insightful)
People "expect" that just because they don't really realize it can be better. Put it another way: they don't expect that at all, they just accept it.
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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 7
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For writing purposes, I'm considering the AlphaSmart Dana [atpm.com]. It's a PDA-like portable word processor that gets 25 hours of battery life without a backlit screen, which wouldn't be an issue for me since my favorite haunts (Bookstop cafe at Shepherd and W. Alabama, Agoura coffee house at Dunlavy and Westheimer, Borders cafe at Kirby and W. Alabama) are all well-lighted. The other option is a netbook. I'd really like someone to design a low-power laptop that allowed word processing and ssh access, because that's
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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.
Re:Does anyone pay attention to battery life anymo (Score:4, Interesting)
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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.
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SSD's consume a lot less power than HDD's, couple your expanded battery capacity with aggressive power management and you might even be able to get more out of it.
WiFi is probably the next huge power sink after the hard drive, turning that off with the physical switch when you aren't actively browsing would squeeze more juice out of your laptop.
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Yes and no. SSDs use less power, but make it a lot easier to keep the CPU fed, and the CPU uses tons of power on its own.
In my case, "normal use" means having 802.11 running. I'm sure I could get more out of what I have but not at the cost of the utility of having that machine to begin with.
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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.
Re:Does anyone pay attention to battery life anymo (Score:2, Insightful)
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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.
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"People expect 2.5 hours", speak for yourself. I expect at least 7-10 hours of battery time from a laptop, I usually don't need a laptop, but when I do I'm away from a usable outlet for quite some time. Having an additional battery is of course possible, but those can easily weigh in at 1 kg+, I got enough to log around as it is.
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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+.
Hate to sound like a Mac whore (Score:5, Interesting)
Re:Hate to sound like a Mac whore (Score:5, Informative)
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.
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Since I presume that you really mean "VIM", then I have an information which might be interesting to you.
VIM, in its default configuration creates and maintains the "..swp" file. By default it is stored in the same directory were file being edited is. Everything you do in VIM from :w to :w is constantly sent to the .swp file to allow for recover after crash. (File is deleted when you end editing session.) That obviously has an impact on battery life - if you edit file from hard drive. Hard drive will ne
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...what is still far from 4 hours I get with the same workload under Mac OS X....
That is easy to explain. Apple designs the hardware and the software together as a unit. They are able to do the power management exactly to the hardware they have in the machine. Neither Windows or Linux are able to know exactly what kind of power management system for manufacturer designed into the machine.
Re:Hate to sound like a Mac whore (Score:4, Informative)
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.
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In other words, your conjecture is wrong.
That wasn't conjecture. This is my experience of making hard drive sleeping when I work under Linux.
Also, it doesn't matter what mode is used to open a swap file - its syncing is regulated by :help 'swapsync' [sourceforge.net] option. It is set to 'fsync' by default on *nix systems, meaning that fsync() would be called when something new is written to swap file.
You should have applied some really disrupting tuning to your I/O subsystem - for it to delay write out of synced data. This breaks all application's expectati [opengroup.org]
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Well, your opinion, like most people's opinions, does not apply to everyone.
I bought my laptop, with an advertised battery life of 1 hour. That was fine with me, I wasn't ever going to use my laptop someplace there wasn't a power outlet, but I planned on moving my computer a lot.
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Lenovo here (Score:3, Informative)
TP X60 here (Score:2)
Solid 7h on a 5200mAh (70Wh) battery, while browsing, coding and doing other things I usually do when I'm on the university campus a whole day, moving from building to building (there's WiFi everywhere, but almost no freely available power outlets in the older buildings, anyway). PLD Linux, kernel 2.6.27.7, X.org 1.6.0, KDE 3.5.10.
my old Panasonic Toughbook CF-72 (Score:2)
Try a CF-T5 (Score:2)
Instead of complaining... (Score:4, Insightful)
Instead of complaining that the test is rigged, maybe creating processors that draw less power when idle would be a good idea?
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Why? How often is the processor in your laptop idle? When my laptop is turned on, I am doing things. When I stop doing things, I turn it off.
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It is well established that the most efficient use of the processor is "bursting" - heavy usage for short periods followed by long periods of idle. This is, in fact how most OS's work, or at least try to.
Furthermore, unless when you say "doing things" you mean video encoding and compression, or something similarly intensive, you are probably not normally going much above idle for any extended period of time. If your CPU is pegged at 100% for long periods of time, it is an indication of a problem.
Take a lo
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Why? How often is the processor in your laptop idle? When my laptop is turned on, I am doing things. When I stop doing things, I turn it off.
Idle doesn't mean you don't have tasks running, it means time *while* those tasks are running (from your point of view) that they don't have anything to do. It's a whole collections of milliseconds here and there. Take the case of decoding an HD video. Your computer has to decode a frame, and when it's done, the video decoder has nothing to do until that frame is displayed and it's time to move onto the next one. That time is considered idle even though from your point of view, your computer is continuously
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I would suggest scaling down the cpu speed then. Significant power savings. My 1.6GHz Atom runs at 800MHz most of the time, and I am trying to find a way to run it slower.
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If I'm not mistaken, AMD CPUs do just that [wikipedia.org] for many years.
My old AMD Athlon 4200+ X2 normally running at 2.2GHz, quite often falls to 1.1GHz to 220MHz.
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Not only do AMD CPUs do that, but my OS does it for me too.
My Ubuntu laptop with cpudyn and cpufrequtils installed automatically lowers the clockspeed to minimum when the cpu is less than 10% and increases it as it's needed.
I also use cpulimit to make processes always take up only a specific % cpu or less.
A Challenege For AMD (Score:3)
Hey AMD, I have a challenge for you. Instead of bitching about Intel rigging their battery life testing mechanisms, why not design your chips to beat Intel at those very same tests?
Also, frankly, I don't want a CPU that uses a noticeable amount more electricity than others when it's IDLING. So at this point, just for this reason, I'm glad my computer has an Intel chip in it. But if you can beat those tests of Intel's that you say are "unfair", and you win the battery life tests that you say are rigged against you, then you definitely have a one-up on Intel in that rite.
Re:A Challenege For AMD (Score:5, Insightful)
This challenge can be equally turned around.
For the sake of devil's advocacy:
Hey Intel, I have a challenge for you. Instead of rigging your battery life testing mechanisms, why not run your tests like real-world usage would do?
Also, frankly, I don't want a laptop that is unusable out of suspend mode, I want to be able to use my laptop while it's near idling. Yes, I use WIFI, and I also use my laptop to see things I want to see. So at this point, just for this reason, I'm glad my laptop has an Intel chip in it, and I'm glad I get those 2.5 hours of battery life (I'd be interested in after-market quality batteries fyi) I can't see how hard it would be to prove your measurements inaccurate.
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Low voltage AMD CPUs (EE, BE series) consume less power than comparable Intel CPUs. Intel produces LV/ULV CPUs, but they are treated generally as higher-end parts which are present in some truly high-end subnotebooks and rarely found in commonly sold notebooks.
But AMD is simply weak in laptop market - they can't compete now with Intel's grip on market.
Standards (Score:5, Interesting)
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.
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Actually, he made the horses do more intense work they normally performed, then rounded the amount of power a horse could exert upwards. He took great pains not to promise more than he could deliver.
The Model 100 (Score:4, Insightful)
20 hours of rugged computing on the go. (Ok...rugged text entry.....) I want a netbook that captures the spirit of the Model 100.
http://en.wikipedia.org/wiki/TRS-80_Model_100_line [wikipedia.org]
People are still using them (much less, unfortunately) today. I'd say there is a market for a long lasting computing device that is rugged.
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The old palms were great for battery life, but at the cost of being painfully slow. 16mhz slow. I used to have one of the redesigned zires or whatever and it was not terribly reliable, nor would it multitask, etc, but it still lasted for days, even weeks on a charge. I felt like that was a cornerstone in pocketable computing, and now it seems like the idea never really gained much traction. Didn't they make palm based watches? and the fossil watches that connected to MSN? Geeky computer watches are cool, bu
Three Numbers (Score:4, Interesting)
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 /. readers) swear you'll actually get
2. The life every reviewer (and some
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)
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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.
That's because the chips in the laptops actually vary quite a bit. Given two "identical" chips (CPU and GPU are the biggest power consuming chips, so the most likely to influence the battery life), one might draw a few more watts than the other at both peak and idle consumption. The chips will be sold with a spec of what their maximum consumption is, and they're guaranteed to be below that. I doubt most manufacturers test with a worst-case CPU and worst-case GPU and a worst-case battery (whose capacity is s
If you want long battery life... (Score:2)
Get a voltage regulator and a couple deep cycle marine batteries. You'd be amazed what fifty pounds of battery can accomplish. -_- Maybe the problem here is "Battery life" is a poor measurement in the first place. There's no frame of reference, for one, and for two, it varies by how you use it. Miles per Gallon is also affected by your driving style. Why do people assume statistics for computers would somehow be more objective?
In other news, people use laptops in places without a wall outlet? Inconceivable!
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Dear God:
Please don't let me get stuck behind this guy at the Airport security checkpoint
Thanx.
Fifty pounds? (Score:2)
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You've got an electric toilet? Weird, you from Japan or something?
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You've got an electric toilet? Weird, you from Japan or something?
Heaven help him if he gets a short. I imagine water, no pants and surprise electricity is a bad combination.
Well, the machine IS mostly idle (Score:2)
For most users, the machine is probably at a CPU load of less than 7.5% the vast majority of the time. I don't think it's unreasonable at all to rate battery life on the assumption that the machine will almost always be at the lowest P and C states. The wifi and brightness settings are a bit dubious but, they vendors aren't claiming that this what users will actually get. They are just claiming that this is what the machine is capable of. And it is.
Think of this in terms of benchmarking other things. I
Re: (Score:2)
"What if automakers measured gas mileage by rolling their cars downhill with their engines idling?"
What an unfortunate example.
Where battery life matters, on a long flight, 50% brightness, mostly idle and no wifi isn't unreasonable at all.
Gas mileage measurements are generally made on a treadmill inside a building, aren't they? I don't know about you, but I've never driven my car on a treadmill (no wind resistance) and I really don't care what kind of mileage it gets in such circumstances.
Battery are the bane of portables (Score:2)
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NetBooks [feeddistiller.com] @ Feed Distiller [feeddistiller.com]
Quit begging and start barking (Score:2)
If the trade publications weren't such complete and utter whores, they would have developed a legitimate, real-world test of battery life that would drive the industry version into the toilet, where it belongs.
iPod (Score:2)
one guess on long battery life on macbooks (Score:4, Interesting)
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.
How this happens (Score:2)
From TFA:
"The rule of thumb is that in real-world use you get about 50 percent of rated battery life," says Mark Wilson, associate editor at Gizmodo. "It's not that companies are lying, but they're stacking the deck in their favor. [Their claims] are misleading to the general public." That's something to keep in mind next time you're out shopping for a laptop.
Not that they're lying!?! Yes, it is. They're lying and they damned well know it. As long as people, especially reviewers, are willing to give them a pass on clearly deceptive practices like that, they will continue to do it.
They know very well that people's laptops will not be idle with the screen at 20% brightness while in use (if it's going to idle the whole time, why turn it on?). The benchmark was clearly designed to give figures with no relation to reality whatsoever. So, yes, they are lying.
Re: (Score:2)
Apple.
Avoid buying new, just-released model - buy models which are on market for 6+ month. They are generally bug-free.
Though like with any OEM, "shit happens" in Apple's wonderland too: nVidia 8600m debacle, swollen batteries, etc. But their service is quite good - especially compared to what rest of industry provides to private buyers.
Re: (Score:2)
How are the harddrives Apple uses any better than anyone elses? As far as I can tell, they are the exact same drive from the same major manufacturers. If anything, I would expect them to last even shorter in most of Apple's cases, because the drives get no airflow and run really hot.
Re:Oh please. If overhyping a product was a crime. (Score:2)
And if torture was a crime... :P
Re: (Score:2)
Modern fuel injected cars don't use any gasoline whilst rolling down a hill. Actually as long as the car is moving forward and the driver isn't pushing down the accelerator, the injector doesn't give the engine any fuel. Once the revs go too low, fuel is injected and the engine begins to idle.
Re: (Score:3, Informative)
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 whe
Re: (Score:2)
While they don't do that, what they do is almost as bad.
They tune the car perfectly and esentially put it on a rollers in a room. No road, no wind, no hills, just the car sitting in a room under perfect driving conditions.
You mean this? [fueleconomy.gov]
At least in the US, automakers are following federal law. The "rollers" you mention are computer-controlled dynamometers which provide realistic resistance based on the speed of the vehicle, simulating road and air resistance. Not only does indoor testing provide controlled, repeatable conditions, but it makes it possible to test the fuel consumption and pollution much more accurately, by capturing and analyzing the vehicle's exhaust.
If you can't get the rated mileage, you should really lo