    =

    AST RESEARCH, INC.        TECHNICAL BULLETIN # 1373                12-14-95

    =

        Bravo MS 4/66d Fails to Boot with Pentium Overdrive Processor Upgrade

    PROBLEM

    The 83 MHz Pentium Overdrive Processor upgrade may fail in the Bravo MS 4/66d.

    CAUSE

    1. At initial power up, the processor reset line resets too quickly, not allowing
       the system to boot.

    2. The board revision may be lower than that required for a Pentium upgrade.

    SOLUTION

    Call AST's Technical Support at (800) 727-1278 and request a system board
    which matches or exceeds the revision noted below.

    SYSTEMS AFFECTED
    AST PART NUMBER AND DESCRIPTION

    501429-XXX      Premmia MX 4-66d
    501432-XXX      Premmia MX 4-100
    501440-XXX      Bravo MS 4-33s
    501441-XXX      Bravo MS 4-50s
    501442-XXX      Bravo MS 4/66d
    501443-XXX      Bravo MS 4-100T
    501541-XXX      Advantage! CMT 2-66d
    501586-XXX      Bravo MS-L 4-66d
    501611-XXX      Bravo MS 4-50s
    501612-XXX      Bravo MS 4-50s
    501644-XXX      Advantage! CMT 2-66d
    510356-XXX      Bravo MS 4-66d
    501655-XXX      Bravo MS-L 4-50d
    501658-XXX      Bravo MS-T 4-66d
    510678-XXX      Bravo MS 4-66d
    501709-XXX      PIII+ 4-66d
    501803-XXX      PIII4 4-100T

    CAUTION

    This modification should be performed ONLY by a qualified service
    technician.  It is strongly recommended that this Field Change Notice (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 motherboard can be identified by observing the
    revision letter at the end of the nine-digit part number located on the solder
    side of the motherboard.

    PARTS REQUIRED
    AST Part Number         Description                         Revision

    202612-001     PCBA MBD B468 PCI                                                 B
    202612-003     PCBA MBD BMS4-50S 4MB/1MB 5.0V                   H
    202612-004     PCBA MBD BMS4-50S 8MB/1MB 5.0V                   H
    202612-005     PCBA MBD BMS4-66D 4MB/1MB 64K                    J
    202612-006     PCBA MBD BMS4-66D 8MB/1MB 64K                    H
    202612-007     PCBA MBD BMS4-100T 4MB/1MB 64K                   F
    202612-008     PCBA MBD BMS4-100T 8MB/1MB 64K                   F
    202612-009     PCBA MBD BMS4-33S 4MB/1MB 0CACHE                 F
    202612-010     PCBA MBD BMS4-33S 8MB/1MB 0CACHE                 F
    202612-100     PCBA MBD BMS4-00 0MB/1MB 3.3V                    H
    202612-101     PCBA MBD BMS4-00 0MB/1MB 5.0V                    H
    202612-102     PCBA MBD BMS4-33S 0MB/1MB 5.0V                   G
    202637-002     PCBA MBD PRM MX4-66D 8MB 0CACHE5.0               T
    202637-003     PCBA MBD PRM MX4-66D 8MB 256K 5.0V               Z
    202637-004     PCBA MBD PRM MX4-66D 16MB 256K 5.0V              AA
    202637-005     PCBA MBD PRM MX4-100T 8MB 0CACHE 3.3V            U
    202637-006     PCBA MBD PRM MX4-100T 8MB 256K 3.3V              Y
    202637-007     PCBA MBD PRM MX4-100T 16MB 256K 3.3V             Z
    202637-008     PCBA MBD PRM MX4-66DW/WB 8MB 0C 5V               T
    202637-009     PCBA MBD PRM MX4-66DW/WB 8MB 256K 5V             U
    202637-010     PCBA MBD PRM MX4-66DW/WB 16MB 256K 5V            U
    202637-012     PCBA MBD PRM MX4-66D 8MB 0C 5V                   R
    202637-013     PCBA MBD PRM MX4-66D 8MB 256K 5V                 U
    202637-014     PCBA MBD PRM MX4-66D 16MB 256K 5V                W
    202637-015     PCBA MBD PRM MX4-100T 8MB 0C 3V                  R
    202637-016     PCBA MBD PRM MX4-100T 8MB 256K 3V                W
    202637-017     PCBA MBD PRM MX4-100T 16MB 256K 3V               W
    202637-018     PCBA MBD PRM MX4-66DWB 8MB 0C 5V                 P
    202637-019     PCBA MBD PRM MX4-66DWB 8MB 256K 5V               S
    202637-020     PCBA MBD PRM MX4-66DWB 16MB 256K 5V              S
    202637-100     *PCBA MBD PRM MX 0MB/0MB 3.3V                    K
    202637-101     *PCBA MBD PRM MX 0MB/0MB 3.3V                    M
    202637-111     PCBA MBD PRM MX 0MB/0MB 3.3V                     R
    202637-112     PCBA MBD PRM MX 0MB/0MB 5.0V                     R
    202670-001     *PCBA MBD DX2-66 16MB/512K 256KC 5V              D
    202670-002     PCBA MBD DX2-66 16MB/512K 256K 5V                K
    202670-101     *PCBA MBD DX-00 0MB/512K 0CACHE 5V               C
    202670-102     PCBA MBD DX-00 0MB/512K 0C 5V                    J
    202694-003     PCBA MBD BMS-L 4-50D 4MB/1MB 64K 5V              X
    202694-004     PCBA MBD BMS-L 4-50D 8MB/1MB 64K 5V              G
    202694-005     PCBA MBD BMS-L 4-66D 4MB/1MB 64K 5V              G
    202694-006     PCBA MBD BMS-L 4-66D 8MB/1MB 64K 5V              G
    202694-007     PCBA MBD BMS-L 4-66DW/WB 4MB/1MB 64K             G
    202694-008     PCBA MBD BMS-L 4-66DW/WB 8MB/1MB 64K             G
    202694-009     PCBA MBD BMS-L 4-50DW/WB 4MB/1MB 64K             G
    202694-010     PCBA MBD BMS-L 4-50DW/WB 8MB/1MB 64K             G
    202694-011     PCBA MBD BMS-L 4-66D/WB 1MB/1MB 64KRCV           F
    202694-012     PCBA MBD BMS-L 4-66D/WB 4MB/1MB 64KRCV           F
    202694-013     PCBA MBD BMS-L 4-50D 4MB/1MB 64K                 E
    202694-014     PCBA MBD BMS-L 4-50D 8MB/1MB 64K                 E
    202694-015     PCBA MBD BMS-L 4-66D 4MB/1MB 64K                 E
    202694-016     PCBA MBD BMS-L 4-66D 8MB/1MB 64K                 E
    202694-017     PCBA MBD BMS-L 4-66WB 4MB/1MB 64K                E
    202694-018     PCBA MBD BMS-L 4-66WB 8MB/1MB 64K                E
    202694-019     PCBA MBD BMS-L 4-50WB 4MB/1MB 64K                E
    202694-020     PCBA MBD BMS-L 4-50WB 8MB/1MB 64K                E
    202694-101     *PCBA MBD BMS-L 00 0MB 0CACHE 5V                 F
    202694-111     PCBA MBD BMS-L 00 0MB 0C 5V                      S
    202694-112     PCBA MBD BMS-L 00 0MB/1MB 0C  RCV                S
    202695-001     PCBA MBD CMT4-66 8MB/1MB CYRX                    W
    202695-002     PCBA MBD CMT4-66 8MB/1MB CYRX RCVDO              W
    202695-101     *PCBA MBD CMT4-00 0MB/1MB 5.0V                   P
    202695-111     PCBA MBD CMT4-00 0MB/1MB 5.0V                    U
    202695-112     *PCBA MBD CMT4-00 0MB/1MB 5V  RCV                T
    202705-001     PCBA MBD BMS 4-50D 4MB/1MB 64K                   F
    202705-002     PCBA MBD BMS 4-50D 8MB/1MB 64K                   E
    202705-003     PCBA MBD BMS 4-66D 4MB/1MB 64K                   F
    202705-004     PCBA MBD BMS 4-66D 8MB/1MB 64K                   F
    202705-005     PCBA MBD BMS 4-50S 4MB/1MB 0CACHE5.0V            E
    202705-006     PCBA MBD BMS 4-50S 4MB/1MB 0CACHE5.0V            E
    202705-007     PCBA MBD BMS 4-100T 4MB/1MB 64K                  B
    202705-008     PCBA MBD BMS 4-100T 8MB/1MB 64K                  B
    202705-009     PCBA MBD BMS 4-33S 4MB/1MB 64K                   D
    202705-010     PCBA MBD BMS 4-33S 8MB/1MB 64K                   D
    202705-011     PCBA MBD BMS 4-66D 8MB/1MB 256K AA               F
    202705-012     PCBA MBD BMS 4-66D 16MB/1MB 256K AA              G
    202705-013     PCBA MBD BMS 4-66D W/WB 4MB/1MB 64K              F
    202705-014     PCBA MBD BMS 4-66D W/WB 8MB/1MB 64K              F
    202705-017     PCBA MBD BMS 4-50S 8MB/1MB 256K                  F
    202705-018     PCBA MBD BMS 4-66DW 8MB/1MB 64KRCV               G
    202705-019     PCBA MBD BMS 4-66DW 4MB/1MB 64KRCV               G
    202705-020     PCBA MBD BMS 4-00 1MB 5V RCVDO                   G
    202705-021     PCBA MBD BMS 4-66D 16MB/1MB 256K RCV             H
    202705-022     PCBA MBD BMS 4-100T 8MB/1MB 256K                 E
    202705-023     PCBA MBD BMS 4-66D W/WB 8MB/1MB 256K             E
    202705-024     PCBA MBD BMS 4-66D W/WB 4MB/1MB 256K             D
    202705-025     PCBA MBD BMS 4-100T CRX 4M/1M 256K               A
    202705-026     PCBA MBD BMS 4-100T 4MB/1MB 256K                 A
    202705-100     PCBA MBD BMS 4-00 0MB/1MB 3.3V                   F
    202705-101     PCBA MBD BMS 4-00 0MB/1MB 5.0V                   E
    202705-102     PCBA MBD BMS 4-33S 0MB/1MB 5.0V                  B
    202705-103     PCBA MBD BMS 4-00 0MB/1MB 5V RCVIDEO             F
    202705-104     PCBA MBD BMS 4-00 0MB/1MB 3.3V CRX               A
    202705-104     PCBA MBD BMS 4-00 0MB/1MB 3.3V CRX               A

    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.

    Remove the system board according to procedures approved and prescribed
    by AST Research, Inc.  Reassemble the system.

    CHECK-OUT PROCEDURE

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

    NOTE

    Warranty reimbursement for this FCN requires prior AST Research, Inc.
    approval.

    The warranty on this system will become VOID if this FCN is completed by
    ANYONE other than an AST Authorized Service Center.