In Windows Vista, an Ultra DMA Mode 5 device may perform only at the speed of an Ultra DMA Mode 2 device after you swap devices.
This problem occurs on an IBM ThinkPad mobile PC or on a Lenovo ThinkPad mobile PC if the following conditions are true:
You start the computer with an Ultra DMA Mode 2 device in the Ultrabay swappable drive bay. For example, you start the computer with an optical drive in the drive bay.
You eject the Ultra DMA Mode 2 device from the drive bay and insert an Ultra DMA Mode 5 device in the drive bay. For example, you insert a hard disk drive in the drive bay.
When these conditions are true, the transfer mode stays at the slower Ultra DMA Mode 2 speed. The system does not correctly use the faster Ultra DMA Mode 5 speed.
Service pack information
To 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:
935791 How to obtain the latest Windows Vista service pack
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
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:
Note 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.
The 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.
To work around this problem, start the computer with the Ultra DMA Mode 5 drive in the Ultrabay drive bay.
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 more information about how hotfix packages are named, click the following article number to view the article in the Microsoft Knowledge Base:
816915 New file naming schema for Microsoft Windows software update packages
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
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.
For help with system performance issues in Windows Vista, visit the following Microsoft web page:
Windows Vista Home Basic, Windows Vista Home Premium, Windows Vista Ultimate, Windows Vista Business, Windows Vista Enterprise, Windows Vista Starter, Windows Vista Home Basic 64-bit Edition, Windows Vista Home Premium 64-bit Edition, Windows Vista Ultimate 64-bit Edition, Windows Vista Enterprise 64-bit Edition