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    AST RESEAARCH, INC.          TECHNICAL BULLETIN # 1032                 12-8-94

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                FLOPPY ERRORS ON BRAVO LC WITH ATI MACH64 VLB VIDEO ADAPTER

    PROBLEM:        After installing an ATI Mach64 VLB Pro Turbo video adapter
                    board in the AST Bravo LC system, the system reports read and
                    write error messages accessing the floppy drive.

    CAUSE:          The address line buffers on the Mach64 (and Mach32) VLB video
                    adapters cause the lines to float, also causing the source and
                    destination addresses of a DMA transfer to change unexpectedly.

                    The ATI board (part number 109-26900-20) may be failing.
                    Locate the ATI part number on the upper right corner of the
                    component side of the board.

    SYSTEMS
    AFFECTED:           AST
                    PART NUMBER       DESCRIPTION

                    501378-XXX      BRAVO LC 486/33S
                    501379-XXX      BRAVO LC 486/33
                    501380-XXX      BRAVO LC486/66D
                    501381-XXX      BRAVO LC486/100t
                    501433-XXX      BRAVO LC486/50S
                    501437-XXX      BRAVO LC486DX4-100MPC
                    501444-XXX      BRAVO LC486DX4-100MPC

    SOLUTION:       Contact ATI at (905) 882-2600 and request a Return Material
                    Authorization (RMA) number for the ATI video board (part
                    number 109-26900-30 or later). This version of the video board
                    will work properly.