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Power settings in a laptop will be in the Control Panel and also in the BIOS. Changing them requires checking both areas.

Hi, I've noticed my old laptop when connected to the internet runs slower when using the battery compared with AC power. Most noticeably when watching videos, YouTube etc. I've tried googling for a solution and have changed some settings in power management to try to compensate, but to no avail. I even downloaded a program called 'Speedswitchxp' which claims to solve this problem but it hasn't. As soon as I pull the AC power from the laptop, the screen noticeably dims, even when battery is fully charged (brand new battery, by the way). It's an old Dell Inspiron 1000, running Windows XP.

In this excerpt from Answercast #37, I look at the reason for power settings in a laptop and how to reconfigure them for more power.

Slower on battery

The short answer is, "I'm not at all surprised."

Many laptops will intentionally cut down their power usage when they are not plugged into AC power.

  • That is intentional, specifically to lengthen the battery life.

Normally, there are power management settings you can control in Windows, in the Control Panel under Power Management. Sometimes, there are additional power management settings that are not actually available through Windows, but are part of the system BIOS instead.

Change BIOS settings

What I would recommend you do – if you are certain that you're willing to trade off a shorter battery life for more processing power when you're not connected to power – is:

  • Go into your computer's BIOS and look specifically for Power management or APC (Advanced Power Management Control, I think it is) settings that may allow you to tune exactly how the computer reacts to a lack of landline power: of AC power.

The battery will need to be recharged more frequently, in that case. It won't last as long, but it should give you the power. It should give you the processing power you're looking for.

  • You may need to look in the BIOS for some settings that Windows may not be aware of, or may not have access to.

Check Windows settings

  • You definitely want to look in Control Panel, Power Management Utilities (which I think you've already done).

Between the two of those, you should be able to tell the computer to go ahead and use as much as power as it needs – whether it's plugged in or not.

End of Answercast #37 Back to – Audio Segment

Article C5619 - July 23, 2012 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

July 24, 2012 2:48 PM

Some manufacturers also include their own power management utilities to change the BIOS power settings. For example, my Lenovo system has a mfg. supplied applet called "Power Manager" to change the various BIOS power settings from within the Windows environment without having to reboot.

December 27, 2012 10:45 AM

hello sir.
my laptop work correctly but when charging is on other time it's very slow plz help me
when the it slow then in all the media players videos all play slowly................
plz help me....

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