Intel Motherboards Using
82371SB PIIX3 Component

Updated: Wednesday, May 1, 1996 


Description

The retail version of Microsoft Windows* 95 may not recognize
the Intel 82371SB PIIX3 IDE controller on Intel motherboards,
causing the BIOS to disable the secondary IDE channel. This can
result in IDE devices (such as CD-ROM drives) not being detected
or disappearing after the system is rebooted.

This affects only the retail version of Windows 95. The OEM
version has an updated MSHDC.INF file included in the OPK
release and is not affected by this issue. 

Root Cause

The 82371SB is not included in the list of IDE controllers in the
MSHDC.INF file shipped with the retail version of Windows 95.
During installation, Windows 95 sees the IDE functionality but can't
identify the exact controller type. It enables the primary IDE
channel of the 82371SB, but assumes that the secondary IDE
channel belongs to a non-plug and play ISA IDE controller.
Windows 95 then adds this information to the plug and play
configuration area. When the system is rebooted, the motherboard
BIOS interprets this information as indicating an ISA IDE
expansion card has been installed, and disables the onboard
secondary IDE channel -- rendering any devices on this channel
inaccessible. The most common symptom is that the CD-ROM
drive will not be recognized by Windows 95 after rebooting the
system.

Affected Products

This issue affects all Intel motherboard products with the 82371SB
component.

Workaround / Action

To determine how the system has been configured, look in the
Windows 95 Device Manager (click Start, Settings, Control
Panel, double click on the System icon, then click on the Device
Manager tab). Double click on Hard Disk Controllers. If you
see the following drivers listed, the system has NOT been
configured correctly:

        Hard Disk Controllers
                -Primary IDE Controller (single FIFO)
                -Standard Dual PCI IDE Controller
                -Standard IDE/ESDI Hard Disk Controller

An Install Wizard has been developed that adds an entry for the
82371SB IDE controller into the MSHDC.INF file. This utility (in
self-extracting zip file format) is available from the Intel FTP site at
ftp://ftp.intel.com/pub/patch/ideinfup.exe, or from the Intel BBS
(503-264-7999). Download this utility and follow the instructions
to update the hard drive configuration file.

You can also get it here from the Tyan FTP site.

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