Battery observations in Vista and XP


Vista_powerI’ve been reading comments here and there on the web about less battery life when running Vista and just got a note from Hector along the same lines. Hector tells me that he’s using the Samsung Q1 with the 6-cell battery and notices that the OS reports a difference in the remaining runtime:

  • XP Tablet Edition 2005: between 6:50 and 7:25 on a full charge.
  • Vista: 5:49 on a full charge.

Just for kicks, I did the same on the Q1P with the 3-cell battery (WiFi on) a few minutes ago:

  • XP Tablet Edition 2005: between 2:49 and 3:02 on a full charge
  • Vista: 2:17 on a full charge

The Windows Vista Team Blog mentions that Vista sets the WiFi adapter power settings at "Maximum Performance", which could be the culprit, although the blog post indicates that this setting has nothing to do with additional battery drain. ArsTechnica delves into the details as well and alludes to a newly implemented "sleep" mode in the 802.11 spec. I’ll be doing additional research but I’d be curious to see what current Vista RTM users are finding.




Hey guys. I had exactly the same problem at 50%.. Then i suddenly remembered; When I installed the drivers for my laptop, I installed another battery management app. SmartBattery. So i uninstalled it, and now everything works..

So guys, please check what applications and drivers you have installed.


The battery saver do not show any message when the battery gets fully charged.


I’ve both had that problem like Hicham.. I’ve a Fujitsu Siemens notebooke too, but it seems only softwere for me, cause when i enter BIOS the battery can fully be charged from there.. I’ve those problems on Vista only, and when I’ve gone back to an early system restoration point it seems to work properly from now.. Now, my battery is fully charged, a green led shows that under the LCD panel, nad Vista say that its fully charged now for a 2 hours about.. I hope its softwere.. Now im waiting for futher problems to solve, but not with battery and not with hardweew plz.. xDD Sorry for my english, byby


My Laptop with windows vista experience similar problem but I think that is more serious. the batery signal shows that the battery is charging, same as the icon, it sais : plugged and charging, but the percentages are always going down untill 0.
even if I tried to unplug and plug again nothing happen. worst, when I take off the battery from the Fujitju SIEMENS laptop, I cant start it with the corde correctly connected!
This started happening after showing the Plugged In Not Charging problem and went till 5% when I decided to shut it down, I left it overnight to charge in the morning I could not start my computer untill 20h in the evening. when it showed battery at 90% level after writing this message it is at 57% in power saver mode. Do you think it is hardware or software? How can I work with the corde without the battery?

Steve Purpura

I have a Lenovo ThinkPad X60S with the highest capacity battery installed. I’ve been running Vista Ultimate RTM for about a week, and I saw reduction in battery life in a typical day from almost 8 hours to less than 5 hours. One of the big culprits is SearchIndexer.exe, which hits the disk all of the time.

Personally, I don’t understand what SearchIndex.exe is doing. Excluding web pages and email, I update maybe 5 files a day on average (and I’m a heavy computer user).

Part of the reason for the problem is that Lenovo’s power utility didn’t set Indexing to “Power Save”, instead it set it to “Balanced”. You can change this in the advanced settings of the Power Options control panel applet.

I’ve reset this and now I’ll measure what happens.

The net of it is that I wish I didn’t upgrade. I upgraded for Shadow File Copying and a few other utilities, but I may downgrade to get my XP experience back.

Tim Marman

The reported battery life left never quite worked for my m200. Under XP, it would report longer times but then drop dramatically faster at the tail end (less than %25), though I’m sure that’s at least partially attributable to an aging and/or dying battery that I’ve resisted replacing.

I’ve never really trusted the reported amount of time left. These are, after all, estimates.

Someone (hint, hint Kevin) should test the full drain on both and see how accurate those estimates are. It’s possible that, like with file operations, these estimates were made more accurate in Vista (which in my case would account for the rapid drop). And managing expectations is good – it’s better to be more conservative with the estimate and have more gas in the tank than to run out when you expected not to need a charge.

That said, I wonder if prefetch could play a role too – it speeds up the system but potentially leads to more disk I/O that wouldn’t otherwise happen, and disk i/o is one of the more expensive operations from a power perspective. On a related note, if you’re running WMP11/URGE, disabling UrgeMS.exe will help reduce I/O as well (


wondering which version of vista you have used to test this, which beta revision, or was it RTM ?


I just went under the power settings and the indexing is set at High Proformane on battery. that could explain why I also notice that the Q1P feels warmer than when using it under the Tablet Edition 2005. I will have to give it c try in a little while and See what happens.


Kevin and JKK, have you tried to disable the indexing process. Origami team recommended to disable the indexing in UMPC to get a better performance. I think that the indexing probably is the cause of you guys having less battery life.


Kevin, I just tried my 3 Cell battery to see what Vista would read right after a full charge and guess what it reads 2:24 to 2:35 it goes between those readings. On Tablet 2005 it would always show 3:25 to 3:40 and I know I would get about a good 3 hours on the Tablet 2005 using WiFi and bluetooth on. I was doing some work on the Q1P in Vista with WiFi and Bluetooth on using the 3 cell battery and the reading on dropped pretty fast to 89% using it for about a 1/2 hour. Any one of any program for Vista like NHC for Windows?

Dave Z

Well mine was at 90% when it refused to charge, so I’m not sure if it was that or if something else was going on (or maybe it’s 90% and not 95%?). I deleted the Microsoft AC Adapter device and rebooted, and it’s now charging again. I did the same thing on my Averatec laptop (the other one running Vista – that one was down to 20%) and the battery didn’t start charging again until I pulled the battery and put it back in, which I had tried before with no luck. But now both machines are charging like they are supposed to.

I found a post on another site from someone who suggested deleting the AC adapter device, so apparently something is going on there.

Warner Crocker

jk and Dave Z. I agree with jk’s point about not charging if the battery is above a certain level. I’ve seen this on several machines. It is a designed behavior to prevent over charging. I do not know one way or the other if that level is 95% or so.

Kevin, I agree, that would be the expected behavior. I just wish I had had the foresight to do some more testing before leaving XP for Vista on the R2H.


Wow, this is really interesting. But I think that we need some facts. The task bar battery prediction time is not that accurate to take it seriously.


JK, Thanks I noticed that with my 1510 and didn’t know the magic # 95%


Dave Z, like most people, I don’t have my PC on all day while I’m running around, although I probably do have it on most of the time when I’m stationary. I think the “not charging” phenomenon you mention is by design, I saw the same thing under both XP and Vista. The Fuji apparently won’t start charging the battery until it drops below ~95%. I believe this is by design to protect from over-charging, perhaps in light of all the exploding batteries that have been in the news. I have watched this for weeks and this is always the case. Let it drop below that magic level and it will start charging again.

Re: the lower battery times in Vista. I haven’t been running it long enough to give real-world impressions but I too see ~25-30% lower battery remaining time reported by Vista over what I experienced with XP. I had intended to write this up but Kevin beat me to it. My gut feeling is that Vista does shorten the battery life over XP, enough to notice too. I expect we should start hearing about this all over the web soon.

Steve Paine


What run times are you getting? Are they different in Vista and XP or is it just a difference in the battery life reports?
This is still an open question from the ‘LED Screen’ tests of a few weeks ago.


Dave Z

Ok, I’m out.

I just plugged my P1610 back in and noticed that it is no longer charging the battery. If I hover over the battery icon it says “plugged in, not charging”. I have the same issue on my son’s laptop (which is also running Vista), and up until now I just thought that it was a bad battery that needed to be replaced – I didn’t think about it being a Vista problem. A quick search on Google turned up several hits from other people having the same problem though, and that’s pretty much it for me – Vista looks pretty and has some nice new features, but frankly I’m just not interested enough in it to put up with it any longer. Reduced battery life, noticeable performance hit, games that don’t work (an issue on my son’s machine), ridiculously long amount of time to open large installation files (because of the UAC – also only really a problem on my son’s laptop and there are workarounds, but it all piles up), and now charging issues. No way I’m going out of town on business with a laptop that might decide to stop charging its battery!

Not sure if it’s related, but the only thing I changed before plugging it back in was to install the Fujitsu-supplied wireless driver. I have been just using the Vista drivers for the Atheros card, but hoped that maybe the Fujitsu driver had some different power management options (it doesn’t). Don’t know why that would make the machine stop charging the battery, and at this point I’m done wasting time on it – back to XP for me…

Kevin C. Tofel

Warner are you sure you didn’t get the “R-squared-H” model? I hear that one increases performance exponentially! ;) Seriously, that’s very interesting and more of what I would have expected. Vista is touted to have more performance and power savings, not less….

Dave Z

Unfortunately the extended battery for my P1610 arrived the day before I installed Vista, so I didn’t get a chance to test it under XP. With a full charge on Vista though, I’m getting about 5 1/2 hours of battery – a far cry from the “9am – 3:30pm with 58 minutes remaining” report that James gave back in November.

This is with the screen at about 50% brightness, WiFi on, and BT off. I’ll be taking it to Chicago for a 4 day business trip next week, so we’ll see how it does using Bluetooth with my BlackJack and WiFi off. Rather disappointing so far, and if a magical solution doesn’t appear soon I may go back to XP – I’d trade off Vista for a couple of hours more of battery life any day of the week, since as it stands I probably won’t make it through an entire day after draining both the standard and extended batteries. Of course if the stupid screen toggle button actually toggled the backlight under Vista instead of just turning it off, I could use that as I did under XP to extend the battery life by disabling the backlight when I’m not using the machine – but having to lift the screen to reach beneath it and use the hotkeys to turn the backlight back on is more of a pain than it’s worth.

Warner Crocker


Bizarrely, perhaps, on the Asus R2H, I’m getting about 20 minutes more reported on a fully charged battery than I did with XP. I have had no time to really test this or look into it further, but it does fly in the face of what most others are seeing.

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