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Microsoft Looking Into Windows 7 Battery Failures
Jared writes "Microsoft says it is investigating reports of notebooks with poor battery life with Windows 7, as first reported by users on Microsoft TechNet. These users claim their batteries were working just fine under Windows XP and/or Windows Vista, and others are saying that battery problems occur on their new Windows 7 PCs. Under Win7, certain machines spit out the following warning message: 'Consider replacing your battery. There is a problem with your battery, so your computer might shut down suddenly.' The warning is normally issued after using the computer's BIOS to determine whether a battery needs replacement, but in this case it appears the operating system and not the battery is the problem. These customers say their PC's battery life is noticeably lower, with some going as far as to say that it has become completely unusable after a few weeks. To make matters worse, others are reporting that downgrading to an earlier version of Windows doesn't fix the problem."
This article is exactly what happened to me. Battery life started fine. A week later, that message. Within a month the battery went from 90% to 3% and did an emergency hibernate. Moving back to XP didn't fix it either, it burned out that battery. I've since gone back to XP (thankfully I had a spare battery, they don't make my model anymore). I hope they fix this before I buy my next computer.
If you are going to post sensationalist stories at least give them better headlines. How about "Microsoft charged with assault on battery"... or some such. Seriously though, this could be bad if the users don't turn out to be crazies that don't want to admit their batteries just went bad.
Get a web developer
Put Windows 7 on there to give to my inlaws and i thought it was a coincidence that the battery died. still works when plugged in, but battery life is like 10 minutes.
formattted it and put Vista on it because the graphics were glitchy with windows 7 and the problem is still there
in the world, and it's been there since before Windows 7.
I don't think I've ever had a friend, significant other, or family member that actually had a working battery in their laptop after the first 5-6 months or so, leaving them all permanently tethered until their next PC (which would end up that way again after the first 5-6 months).
Meanwhile, my batteries have always lasted the life of the unit with more or less full capacity.
I've long assumed it had something to do with usage patterns and charging habits, but I've not really looked into it more than that. One variable was that they were all using Windows (in some incarnation) and I rarely boot into Windows at all.
STOP . AMERICA . NOW
I put a clean install of Windows 7 on a new HDD in my HP dv7t, which came with Vista. The battery has been fine. I have also deployed several new Win7 laptops, and installed Win7 on two or three other laptops, with no issues.
Software controls how batteries are used/discharged.
http://en.wikipedia.org/wiki/Advanced_Configuration_and_Power_Interface
Clearly the power is leaking out all the windows, they should use quality double paned glass, to help mitigate the problem.
It's either false dichotomies, or the terrorists win, you decide.
This is one of those things that's really hard to pin down.
LiON batteries -- what's used in most laptops and netbooks now -- have different kind of failures and limits from the older NiCD and so on. Aside from the catastrophic failures that made the news, what happens with LiON is that there are a limited number of charge cycles per cell no matter what you do. The cells generally go around 300 charge cycles before their capacity drops to about half. The controller in the batteries (which prevents them from just bursting in flames all the time) senses this and reports it back to the os.
The result is that when you upgrade the machine, you've already had it a long while and you're not far from that day when suddenly you notice your capacity has dropped to about half and you'd better replace the battery. Your cruising along at 60% then a minute later you're getting the warning that you're out of battery -- one or more cells is no good anymore.
To test this, you'd have to buy a new battery first and then compare life cycles.
btw: Lots of theories about how to make them last longer -- most of the actual experts say to try to keep it at around 40% if you're going to store it and not use it, otherwise just use the machine. The controller won't allow it to overcharge an they have no "memory" per se.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
Lithium Ion batteries do lose their maximum charge over time, that's a fact of physics. How much charge they lose depends on temperature and how much they're charged up.
http://www.batteryuniversity.com/parttwo-34.htm
I'm under the impression that repeatedly charging/discharging the last couple of percent of a litium battery can very much reduce its life. I seem to remember someone from the OLPC project saying they extended battery life by avoiding charging the battery to full charge. As an anecdote, I have a laptop that I leave plugged in at almost all times. When I do run it on batteries, the battery last about the same amount of time as when I bought it. On the machines that I carry around, use and chjarge regularly, The battery life is significantly reduced after 6 months of use. If I were to hazard a guess, I would think that the OS is constantly charging and discharging teh top couple of percent of abttery capacity. O f course, I'm neither and electrical, or chemical engineer.
Thanks for the interesting link. I was particularly intrigued by the chart indicating how much temperature has an effect on charge level. I'd wager that this is a major cause of a lot of these reported Windows 7 battery problems.
After all, Windows 7 is more resource intensive than XP, especially if you are using Aero Glass. Not only does that mean that CPU usage may be up, but also that the platform it is running on will be using more powerful CPUs. Both of these things result in more waste heat which can leak into the battery. XP, on the other hand, won't be heavily taxing the CPU/GPU under "ordinary use" (e.g., non-game) circumstances, and can run on less-powerful (and thus cooler-running) processors.
If you wanted to play the odds on best possible result -- he should use it tll it hits about 45% and then plug the laptop in and remove the battery, putting it on the shelf until he needs it.
The problems with that are
1. There's no battery in the machine, and it's really easy to pull the cord out the back of a laptop -- and its not really much of a laptop without a battery, is it?
2. The battery won't store charge indefinitely, so he's got to plug it in once in a while and make sure to keep that charge up around 40-50%
3. When he does need the battery, it hasn't got much charge in it so he's got to plan an hour or two ahead of time.
To me, I'd go with the "just use the damn thing" approach, and after a year or two just buy another hundred dollar battery.
For what it's worth, these guys were extremely helpful to me when I looked into this stuff and I've found them good to deal with (http://www.atbatt.com/). They also donate large numbers of 9v batteries to fire departments to give to people with smoke detectors, so I consider that worth some karma points.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
Just chiming in to say that this issue is definitely real. My Dell Vostro battery was about a year and a half old when I installed Windows 7 the first time. When I finally decided to switch fully to 7 it only took about two weeks before I unplugged my computer and got a message that my battery needed to be replaced. The battery until then had about an hour and a half of time on it running the 'balanced' power setting. I noticed the message maybe two to three minutes after unplugging. I was planning to buy a new battery, but if this is real then I hope a class action is in the works because I need a new battery, and this is obviously the reason I need one. Also, since installing 7 I should point out that my battery now only has a seven minute life off ac power, even under Ubuntu 9.10, 8.04, and Windows XP. In response to someone mentioning 'high performance' being the likely culprit, I only ran high performance power management while on ac power.
I understand that, but what specifically about it allows for permanent battery damage? Can commands to discharge and so forth really be issued to the battery in a manner so as to permanently damage and decrease the life of it in a short space of time? Is there no protection at hardware level against it also for example?
If there is no hardware protection then does that not also leave the door open for intentionally malicious software such as viruses and trojans to kill batteries?
I guess my question would've been better phrased as "if it is possible, then why is it possible for software to kill a battery?".
The original marketing slogan "Windows - Life without walls (but definitely with wall adapters) ." was determined unwieldy, and had to be shortened somewhat...
"...there are some things that can beat smartness and foresight. Awkwardness and stupidity can." ~ Mark Twain
My laptop went NEAR a Windows7 box, and immediately died! I like Windows 7, but it must have terrible power stuff there must be in it!!!
When OS X 10.0 beta first came out, it was so much nicer to use than 9 (just being able to wake from sleep in less than 10 seconds was enough alone) that I permanently switched over to it on my G3 Powerbook (Pismo model). However, that being the "previous" model at the time (I bought one of the last ones), they didn't have the power management working right, and it used up the battery noticeably more when in sleep. But that wasn't the big problem.
In the last month before the initial one-year warranty was expiring, I was running it off of battery. When the battery got down to 75%, it suddenly went to 1%. I thought it was a glitch or something. After that, the battery only started crashing sooner. At that time, due to the model being out of sale for a year, Apple (apparently) stopping production of replacement batteries (a really stupid idea right there), and (presumably) other people having their batteries die at the same time, getting a new battery was like pulling teeth... from an elephant.
This illustrates one of the failure modes with LiIon batteries. When they wear out, they will charge to 100%, but crash during the discharge cycle. Part of the problem was that Apple had their laptops topping off the batteries whenever not at 100% (later on, Apple made a change so as not to top it off when already at 95% of better), and part of the problem was that the incomplete power-down during sleep caused the battery to go through cycles faster.
Also, LiIon batteries have a shelf life of a couple of years even if not used. It's possible that some of these people might have had an older laptop, but the summary specifically mentions new W7 laptops, and Windows computers are usually traded up more often than Macs. But I'm sort of surprised that the BIOS wouldn't be handling the power management exactly the same whether XP or 7 was used.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
ACPI does not normally (and from what I've seen, never) export any controls over battery charging, or even allow the user to choose power supply. The job of handling power is usually done by the embedded controller and its firmware, which also handles any charging (along with circuitry designed specifically for the job). This is designed for optimal performance of the system in mind and usually works very well. The operating system just monitors the state of the power supply and can make demand-related decisions (CPU power-state, screen brightness, sleep/shutdown) based upon a chosen policy. If batteries really are packing up early in the manner suggested, this is more likely down to a hardware/firmware/miscellaneous-ACPI-EC-horkage defect in the notebook itself, not the operating system.
That and certain drives also have a mind of their own and ignore any hdparm APM setting after a short while in favour of their own, absurdly aggressive setting. One I have (by default) unloads after 8 seconds of inactivity and the only way to change it is by some obscure DOS utility that I can't get to work. 8 seconds is crazy-low, and because the typical interval for disc activity on a Linux system under enthusiastic use is typically 10-15 seconds (or even when a bit idle, as lots of other things touch the filesystem in the backgrounds), the heads spend a lot of time loading and unloading. It's possible to tune the Linux VM subsystem to ouch the disc less often, but in practise doesn't make much of a difference. Windows XP does exactly the same. The disc manufacturer says Linux should not wake up the disc so frequently, but I don't see how that squares with the way a modern, multitasking operating system works; things touch the filesystem, and this must be synced in good time (I don't want 30 seconds' worth of dirty data just sitting in RAM). And besides, disc manufacturers should just make discs and leave VM policy to kernel designers.
I had to buy a new battery after upgrading to Snow Leopard as it told me that the battery needs to be serviced. It could have been a mere coincidence since the battery was more than a year old and functioned at about 60% capacity before the upgrade.
My HP 2510p went from an absolute maximum of 4 hours life to nearly 7 hours when I installed Win7. I never let it go below 20% or charge above 80% if I can help it and if I'm working plugged in I've taken to removing the battery altogether so that the heat the system generates won't contribute to shortening battery life. I certainly wouldn't ever go back to Vista or XP for the sake of a battery. Win7's power management is vastly superior. (I wonder if people having problems upgraded to Win7 vs. performed a fresh install?)