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AST RESEARCH, INC.        FIELD CHANGE NOTICE #0038A                 11-12-90

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                         AST PREMIUM 486/25 CPU CARD


PURPOSE:            To eliminate possible system lock-ups or improper
                    operation of the Premium 486/25 CPU board when running
                    certain applications or operation systems.

                    All revisions of the Premium 486/25 CPU may exhibit the
                    above problems when running programs such as IBM's OS/2
                    version 1.2, AST's OS/2 version 1.2 or trying to load
                    Novell Netware 3.0 NET$OS.EXE from the A: drive.

                    The problem is fixed when the socketed PAL chip at
                    location U51 on the PREMIUM 486/25 CPU board is upgraded.

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 damages to
                    the system and its components or loss of data caused by
                    improper or faulty installation of this FCN.

PREREQUISITES:      None

TIME REQUIRED:      .5 hours

ASSEMBLIES
AFFECTED:           202361-002 Rev. "L" or below

STATUS              The revision level of the Premium 486/25 CPU board can be
VERIFICATION:       identified by observing the label next to the CPU board
                    (part number 202361-002).  Those boards that are revision
                    "M" do not require this FCN.

PARTS                          AST
REQUIRED:           QTY    PART NUMBER    REV     DESCRIPTION

                     1     107101-761      A      IC (PAL)

TOOLS
REQUIRED:           Standard computer tools.

DIAGNOSTICS
REQUIRED:           None

INSTALLATION        Following procedures outlined in the Premium 486/25
PROCEDURE:          User's Manual:

                    1.  Remove the top cover from the system.

                    2.  Remove the CPU board.

                    3.  Locate the socketed IC chip at location U51 on the
                        CPU board.

                    4.  Using a standard chip removal tool, remove the IC
                        chip (part number 107101-688 from the socket location
                        U51 and replace with the new IC chip (part number
                        107101-761).

                    5.  Replace the CPU card and top cover.

CHECK-OUT           To verify proper operation of the system upon completion
PROCEDURE:          of this FCN, follow the set-up and test procedures
                    described in the AST Premium 486/25 User's Manual.