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Power consumption may be slightly more than expected on a portable Windows Vista-based computer that uses a SATA hard disk that does not support Host-Initiated Link Power Management
Article ID: 932079 - View products that this article applies to.
Important This article contains information about how to modify the registry. Make sure that you back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs. For more information about how to back up, restore, and modify the registry, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/256986/ )Description of the Microsoft Windows registry
Power consumption may be slightly more than expected on a portable Windows Vista-based computer. This problem occurs if the following conditions are true:
Note The increased power consumption is small and may not be noticeable to a typical user.
This problem may occur if the SATA hard disk does not support HIPM. In this case, Windows Vista may not use DIPM for power management. Therefore, the Windows Vista power management feature is less able to efficiently manage power consumption.
Note This problem may also occur if you modify a registry key to disable HIPM. This article does not address the scenario in which HIPM is disabled by using a registry key.
Service pack informationTo resolve this problem, obtain the latest service pack for Windows Vista. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/935791/ )How to obtain the latest Windows Vista service pack
Hotfix informationWarning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
To enable this hotfix, you must manually enable DIPM in the registry.
Note Do not apply this registry change if the hard disk does not support DIPM. Unexpected problems may occur if you apply this registry change and the hard disk does not support DIPM. Contact the manufacturer of the hard disk for more information about how to determine whether the hard disk supports DIPM.
For information about your hardware manufacturer, visit the following Web site:
http://support.microsoft.com/gp/vendors/en-usMicrosoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
To manually enable DIPM, add a registry entry named DipmEnabled, if one does not already exist. If the registry entry exists, you must give it a value of 1. To add or modify the DipmEnabled registry entry, follow these steps:
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:
http://support.microsoft.com/contactus/?ws=supportNote The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
File informationThe English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.
Windows Vista, x86-based versions
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Windows Vista, 64-bit versions
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Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Windows Vista Service Pack 1.
For help with power consumption and battery life problems in Windows Vista, visit the following Microsoft Web page:
Fix problems in which power consumption is more than expected or the battery life is shortFor more information about how hotfix packages are named, click the following article number to view the article in the Microsoft Knowledge Base:
816915For more information, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/816915/ )New file naming schema for Microsoft Windows software update packages
(http://support.microsoft.com/kb/824684/ )Description of the standard terminology that is used to describe Microsoft software updates
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.
Article ID: 932079 - Last Review: July 14, 2008 - Revision: 4.2