Q170324: CMD PCI-0646U Accessed in Compatibility Mode in OSR2

Article: Q170324
Product(s): Microsoft Windows 95.x Retail Product
Version(s): 2,2.1
Operating System(s): 
Keyword(s): kbhw osr2 win95 kbHardwarekbfixlist
Last Modified: 25-MAR-2002

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The information in this article applies to:

- Microsoft Windows 95 OEM Service Release, versions 2, 2.1 
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SYMPTOMS
========

When you use an IDE controller based on the CMD PCI-0646U chip set in Windows 95
OEM Service Release 2 or 2.1 (OSR2), the controller is not recognized,
protected-mode drivers are not loaded, and the controller is accessed in
Compatibility (BIOS) mode.

CAUSE
=====

The CMD PCI-0646U chip set uses some control registers in a different manner
from earlier models of CMD controllers. The Windows PCI driver accesses these
registers in a way that causes it not to recognize this controller.

RESOLUTION
==========


STATUS
======

This problem no longer occurs in Windows 98. To resolve this problem, install
the current version of Windows. For information about the current version of
Windows, visit http://www.microsoft.com/windows.

MORE INFORMATION
================


Additional query words: 95 chipset

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Keywords          : kbhw osr2 win95 kbHardware kbfixlist
Technology        : kbWin95search kbOPKSearch kbWin95OPKOSR2 kbWin95OPKOSR210
Version           : :2,2.1
Issue type        : kbprb

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