Q142694: CPU Write-Back Cache Disabled on Certain Cyrix Processors

Article: Q142694
Product(s): Microsoft Windows NT
Version(s): 4.0
Operating System(s): 
Keyword(s): kb3rdparty kbhw kbHardware
Last Modified: 08-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Server version 4.0 
- Microsoft Windows NT Workstation version 4.0 
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SUMMARY
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When initializing certain Cyrix processors, Windows NT 4.0 will disable the CPU
write-back cache to prevent serious system problems.

MORE INFORMATION
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Certain Cyrix processors are known to cause serious problems with Windows NT
4.0.


If Windows NT detects certain Cyrix processor steppings, it will disable the L1
w/b (write-back) cache.

This will reduce performance but will guard against systemwide problems caused by
the write-back cache, thus preventing data-loss.

The Cyrix products discussed here are manufactured by Cyrix Corporation, a vendor
independent of Microsoft; we make no warranty, implied or otherwise, regarding
these products' performance or reliability.

Additional query words: prodnt cyrix write-back processor

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Keywords          : kb3rdparty kbhw kbHardware 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : 4.0

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