    AST RESEARCH, INC.        TECHNICAL BULLETIN # 1529          7-12-96

    TITLE: SCO OpenServer 5.0 with IDE HD > 2.1GB

    SUMMARY

       SCO OpenServer, version 5.0, does not install onto a Western
       Digital model WD32500 2.5GB drive.

       This issue applies to all systems regardless of manufacturer.

    ISSUE

       During installation of SCO OpenServer, version 5.0, onto a Western
       Digital model WD32500 IDE drive, the system generates the following
       error message:

            WARNING: hd:  no root disk controller

       After continuing past this message, the system generates the
       following error message:

            NOTICE: ram: No space on device 31/50

       At this point, the system aborts the installation and prompts the
       user to turn OFF the system.

    BACKGROUND

       SCO does not support IDE hard drives larger than 2.1GB.

       SCO has verified this limitation of the Unix Operating System and
       will provide an updated IDE driver when development is complete.
       The user is instructed to contact SCO for further information.

    ACTION

       In the absence of the updated driver, the user has two options
       to install SCO ODT on this particular Western Digital drive:

       1. Change the jumper settings on the hard disk to the
          "Special Settings".  Refer to the label on the hard disk.
          Place the jumpers on positions 1-2 AND 3-4 to reduces the hard
          disk capacity from 2.5GB to 2.1GB.

       OR

       2. Do not change the jumper settings.  To install SCO, at boot time,
          add "biosgeom" parameters.  (Please refer to SCO OpenServer
          Handbook, part number AU20000P003, page 280).  This will override
          the root disk geometry stored in BIOS.  Although  2.5GB full
          capacity is calculated, and the value is input to biosgeom
          parameter settings, SCO will still only recognize 2.1GB capacity
          during the installation.

    NOTES

       N/A

    TAN N/A

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