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    AST RESEARCH, INC.          TECHNICAL BULLETIN # 1116              3-28-95

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    			 HARD DRIVE BAY ADAPTER PROBLEM IN DESKTOP SYSTEMS

    PROBLEM

    Desktop systems may take between 2 and 5 minutes to boot if there is no hard
    drive in the hard drive bay adapter.

    CAUSE

    The BIOS on the hard drive bay adapter is waiting for BIT 7 of Port 177H to go
    low.

    SYSTEMS AFFECTED
    AST PART NUMBER AND DESCRIPTION

    Desktop systems using hard disk drive bay adapters, revision X03.

    SOLUTION

    Replace the hard drive bay adapter P/N 202540-002, revision X03, with revision
    X04 or higher.  See part number below.

    CAUTION

    This modification should be performed by a qualified service technician.
    It is strongly recommended that this FCN be completed by an AST Authorized
    Service Center.  In no case will AST Research, Inc. be liable for damage to
    the system and its components, or loss of data caused by improper modification.

    PREREQUISITES

    A full backup of all data on the hard drive in the computer is strongly
    suggested.

    TIME REQUIRED

    30 minutes.

    STATUS VERIFICATION

    The revision level of the AST hard drive bay adapter can be identified by
    observing the revision letter at the end of the nine-digit part number located
    on the solder side of the hard drive bay adapter.

    PARTS REQUIRED
    AST PART NUMBER AND DESCRIPTION                     REVISION

    202540-002     PCBA HARD DRIVE BAY ADAPTER        X04 or greater

    TOOLS REQUIRED:     Standard computer tools.

    INSTALLATION PROCEDURE

    Refer to the system Hardware Maintenance Manual.

    Removal and replacement of system "Field Replaceable Units" (FRUs) should only
    be performed according to the installation procedures approved and prescribed
    by AST Research, Inc.

    CHECK-OUT PROCEDURE

    To verify proper operation of the system upon completion, follow the setup and
    test procedures described in the AST User's Manual.

    NOTE

    Warranty reimbursement requires prior AST Research, Inc. approval.