AMD CPUID Check for the AMD Athlon Chip Now Allows Write-Combining Feature

ID: Q231949

The information in this article applies to:

Microsoft Windows NT Server, Enterprise Edition version 4.0
Microsoft Windows NT Server version 4.0

SYMPTOMS

When you start your computer, Windows NT 4.0 does a CPUID check for an Intel processor. If the processor is a Pentium II or Pentium III, code paths are opened to allow write-combining. The AMD Athlon processor also has the write-combining functionality, but the feature is not enabled when the kernel is initialized.

CAUSE

This problem occurs because the code was not in place to enable the write-combining functionality for the AMD Athlon processor.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to:

http://www.microsoft.com/Windows/ServicePacks/

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. This problem was first corrected in Windows NT 4.0 Service Pack 6.

MORE INFORMATION

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Additional query words:

Keywords : kbbug4.00 kbfix4.00
Version : winnt:4.0
Platform : winnt
Issue type : kbbug