Adjusting power consumption on laptops

Mike Jackman offers tips for powering down Windows to make the laptop battery power last and last and last.

On July 19th Mike Jackman offered tips for powering down Windows to make your laptop battery last and last and last.If you couldn’t join us then, enjoy the transcript; and we hope to see you on our next live Guild Meeting. You can find a schedule of Guild Meetings in your weekly TechProGuild Notes TechMail or on the Guild Meeting calendar.

On July 19th Mike Jackman offered tips for powering down Windows to make your laptop battery last and last and last. If you couldn’t join us then, enjoy the transcript; and we hope to see you on our next live Guild Meeting. You can find a schedule of Guild Meetings in your weekly TechProGuild Notes TechMail or on the Guild Meeting calendar.

Note: TechProGuild edits Guild Meeting transcripts for clarity.

Energizing your laptop
MODERATOR: Welcome to today's Guild Meeting! TechRepublic's own Mike Jackman is here to discuss "Extending your battery life." He has plenty of tips for powering down Windows to make your battery's power last much longer.

MIKE JACKMAN: Thanks, mod. We can try to make laptops like the Energizer Bunny—just keeps going and going, but laptops present some challenges. I'm hoping, also, that you'll offer your own problems and suggestions.

Battery lifetimes
MIKE JACKMAN: Do you use a laptop frequently?

NICKCM97: I use a laptop every day at work.

MIKE JACKMAN: Thanks, nickcm97. How long does your battery last, typically?

NICKCM97: About three and a half hours.

MIKE JACKMAN: That's actually pretty good. What type of laptop is it, and if you know, what type of battery?

NICKCM97: It's a Compaq Prosignia 161. How do I determine the battery type?

MIKE JACKMAN: You'd have to take it out and look at the label, but I don't recommend that if you're using it right now. Typically, laptops will use Lithium Ion batteries or Nickel Metal Hydrides.

NICKCM97: What's the difference?

MIKE JACKMAN: Nickcm97, the difference is the chemistry of the battery. Lithium Ion batteries are typically lighter and last longer, as well as lasting through more recharge cycles.

NAMASTE: I use the laptop at work as a workstation and on the road.

JCARLISLE: I've got a Dell Inspiron 7000 and can get about 2.5 hours out of it, maybe as many as three if I’m lucky. I've got a Tandy 200 that will run for a month with eight AAs.

MIKE JACKMAN: One way to begin to extend the battery life is to make sure your battery is conditioned. Some laptops, like my Compaq Armada, have a setting to condition the battery. Conditioning is important because it discharges and then recharges your battery a number of times. For the nickel batteries, this reduces crystal formation that saps power in the long run. It also configures the battery meter so that it gives accurate readings.

JCARLISLE: What if your computer doesn’t have a utility to do that?

MIKE JACKMAN: JCarlisle, it would be worth checking the computer manufacturer's download site to see if there are utilities available; if not, there are some available at Linux is now offering some power management tools. Check out and's app listing, also. With a few other techniques, you can squeeze maybe another hour out of your battery.

NICKCM97: What about NetWare?

MIKE JACKMAN: Well, you probably won't find many people running NetWare on a laptop.

Adjusting configurations to extend battery life
JCARLISLE: Which device consumes more power on a laptop? Is it the display, CPU, or hard drive?

MIKE JACKMAN: JCarlisle, I don't know specifically which consumes more—it depends on the configuration. I recommend tweaking all three to extend battery life. Let's start with the display. Repainting the screen consumes power, so one way to reduce that is to take off wallpaper and use a plain background. The same with screen savers; turn off your screen savers when it's critical to save power, and if you must have one, use a blank screen saver. One problem with screen savers is that when you are using the computer, there's a background timer running to check if the computer is idle and to count down to when the screen saver should start. This consumes processor cycles, thus power.

JCARLISLE: Does screen resolution or color depth make a difference?

MIKE JACKMAN: Good question, JCarlisle. Yes, it does. Everything incrementally makes a difference. If you can afford to, that is, if you're not doing graphic-intensive work, lower your color resolution to 256 colors. Also, turn off special effects, like moving the contents of windows while dragging. Those changes are simple, and they help.

JCARLISLE: Will the difference be noticeable? Are we talking seconds or minutes?

MIKE JACKMAN: At this point, the changes start to add up. A few minutes makes a difference when your computer is about to go blank!

Improving your battery’s life
NICKCM97: What's the single thing I can do to best improve my battery life?

MIKE JACKMAN: There are a couple of biggies, nickcm97, so I'll talk about those. If you have power management, look to see if you can change these settings. Next, reduce your CPU speed. Then, lower the brightness of your LCD display. These will save a lot.

JLWALLEN: I have a question. Do you advocate going into console mode (i.e., DOS or LCI) when battery life is low?

MIKE JACKMAN: Jlwallen, GUIs are always like vampires, sucking the life out of machines. If you can work in DOS or Linux console, by all means do so. Your batteries will last a lot longer.

JCARLISLE: What BIOS settings can I change to improve battery life? Or what about Power Management settings in Windows 98?

MIKE JACKMAN: Depending on the BIOS, you can make many of the same changes, including some we haven't talked about, like putting your computer in suspend mode and sleep mode after awhile.

There's another cool tweak: Go out and get a program called CPUidle. This program optimizes your CPU. It cycles it down when demand is low. Originally, it was written to keep them cool, but you get power savings as well. On the Armada, I can make the 500-MH Pentium run at 250 if I want, sort of a reverse overclocking.

JLWALLEN: What kind of tools do you have in DOS that allow you to work? For example, if you are in the middle of writing a text file, do you use Edit?

JCARLISLE: Edit works great with basic Text files. Unless you’re a masochist, then you can use EDLIN.

MIKE JACKMAN: Hey, for DOS lovers, there's always WordPerfect 4.2.

JCARLISLE: Can you still get a copy of WP 4.2? Where would you find it?

MIKE JACKMAN: JCarlisle, actually, you can get 4.2. I can't remember the site, but there are places on the Web to get copies of legacy apps.

JCARLISLE: Are these legit copies or pirated rip-offs?

MIKE JACKMAN: I can't answer that for sure. I think maybe the licenses have been superseded or expired. What happens when you have a program that's ancient, say four years old?

JCARLISLE: I would think the license is still valid, no matter how old the program. Doesn’t copyright law hold for 50 years?

MIKE JACKMAN: I’m not sure, jcarlisle.

Adjusting the Conservation Level setting
NCADLE: Have you ever had the opportunity to experiment with batteries in "extreme" conditions?

MIKE JACKMAN: Ncadle, you are too kind. He knows that I've been to the Himalayas with my laptop and learned a lot of this firsthand.

NICKCM97: What sorts of things will be affected by changing the Conservation Level setting on my laptop?

MIKE JACKMAN: Hibernation and suspend mode, chiefly, will affect hard drive use and CPU use. Sometimes, computers have trouble returning from hibernation, though, so I'd use it carefully.

MIKE JACKMAN: One good technique is to make a low power hardware profile. Just copy your existing undocked profile, boot into it, and turn off all the devices you don't need. This means disabling (just in that profile), things like IR ports, com ports, the floppy drive, if you can get away with it, and especially, PC cards. PC cards draw power when they are enabled. If you make a separate profile, you won't have to keep changing your hardware settings.

Power-saving tips
MIKE JACKMAN: By the way, does anyone have any good power-saving tips?

JLWALLEN: PCMCIA services consume a lot of power, so shut them down if you don't need them.

MIKE JACKMAN: Exactly. With all these tips, I've been able to stretch my batteries at least an extra hour. On some machines, you can slap in a second battery. Of course, that helps, too.

ROB.MCPHERSON: Some of the elements for power saving that you mentioned are already there in Safe mode. Can you boot to Windows Safe Mode to conserve power and still have access to the power management tools as needed? Or are these available only in Normal mode?

MIKE JACKMAN: I believe, Rob.mcpherson, that you can. At least the ones I am familiar with are available through the Control Panel in Win 98.

Oh, one other thing I left out—start programs. Check the programs you have that start automatically. Many of these run in the background, such as Norton scheduler and the dreaded Microsoft Quick Finder.

Examining hard drive settings
JCARLISLE: What are the optimum power-down settings you recommend for hard drives and such.

MIKE JACKMAN: Can you elaborate, JCarlisle?

JCARLISLE: What are your recommendations for idle-time settings for hard drives, CPUs, and monitors? How long before the laptop suspends these devices due to inactivity? For example, you don't want to set the hard drive to idle too fast, or it will spend a lot of time powering up and down, which consumes extra life. At the same time, you don’t want the thing sitting and spinning if it doesn’t have to be.

MIKE JACKMAN: JCarlisle, these are settings that I'm not extremely familiar with. How do you usually handle it? I know that one other thing you can do to reduce the number of HD reads and writes is to add more RAM to the machine—more RAM, less swap file activity, that is.

JCARLISLE: I think the best average is around 15 minutes, but it depends on the application. I just thought you might have some suggestions.

Checking your battery’s temperature
NICKCM97: Does temperature affect the rate of battery self-discharge?

MIKE JACKMAN: Temperature, as far as I'm aware, is very important for batteries to run well. It doesn't affect storage so much as efficiency. In lower temperatures, batteries don't function well. We’re not talking very low temperatures either, around 40 degrees, even.

NICKCM97: By following the steps you're outlining, up to what percentage can I increase my battery operating time?

MIKE JACKMAN: I'm thinking that you can increase your battery operating time from 25-40 percent, depending on many factors, such as the amount and type of programs you have running. Eventually, we'll get better power management. When I was at PC Expo, I saw some demos of the Crusoe chip, which is optimized for power conservation. They claim double battery life, for example six to eight hours on standard Lithium Ion batteries.

Exploring new technology
JCARLISLE: Are there any new battery technologies on the horizon that we can look forward to?

MIKE JACKMAN: There's a new version of the Li Ion batteries out. They’re being marketed at the UPS market. They are flexible batteries. They’re on a little pad that sits under your computer and can, I'm told, last eight hours.

The thing that's interesting about batteries is that they don't actually have to be snapped in to your computer. As long as you get the right number of volts in at the right polarity, you can use anything. In Nepal, we carried separate Gel Cel (lead) batteries. We used an inverter, at times, to provide 120 V power for the laptop.

JCARLISLE: Do L-IONs have a memory like the old NiCads?

MIKE JACKMAN: L-IONs, JCarlisle, have no memory.

JCARLISLE: How many yaks does it take to carry the lead batteries necessary to work for an eight-hour day?

MIKE JACKMAN: Yep, that's one drawback of the lead acid batteries: It's tough to carry around 25- or 30-pound batteries just to keep the laptops going. But, hey, if that's what it takes!

Configuring your swap file
MIKE JACKMAN: There's one other trick I've heard of, but I can't verify how well it works: It's to make sure you configure your swap file so that Windows is not managing it. Since Windows changes the size of the swap file on the fly, there's a lot of hard disk activity going on.

JCARLISLE: Now how does that work when the CPU isn’t the main consumer of power on a laptop?

MIKE JACKMAN: JCarlisle, it works beyond the CPU, as I understand it. Their built-in power management actually adjusts the voltage coming in from the power supply. That is, when the CPU is idle, the voltage drops.

CGOLDSMITH: Is this drop from power management real time or elapsed?

MIKE JACKMAN: Cgoldsmith, it is real time, I believe. Check out It's a really exciting breakthrough. I saw it demonstrated on HP, IBM, and other laptops.

Eliminating autosaves
GAIL.FECSO: Does minimizing the number of program autosaves help?

MIKE JACKMAN: Absolutely. There is less HD activity, but don't take too many risks. There are tradeoffs. For instance, you could disable Norton AntiVirus, but not when you're online. Gail, that was a good point I hadn't thought of.

Winding down the meeting
MODERATOR: Time's up for this meeting! Great questions, everyone!

CGOLDSMITH: This meeting has been very informative. Thank you Mjackman and everyone who offered extra tips.

MIKE JACKMAN: Thank you, Cgoldsmith! And thank you all who added your spark to the mix.
Our Guild Meetings feature top-flight professionals leading discussions on interesting and valuable IT issues. You can find a schedule of Guild Meetings in your weekly TechProGuild Notes TechMail, or on the Guild Meeting calendar.

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