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AST RESEARCH, INC.           TECHNICAL BULLETIN # 1043                 1-5-95

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                PREMMIA GX AND CONNER CP30544 540MB IDE HARD DRIVE


PROBLEM:        The Conner CP30544 540MB IDE hard drive will not boot DOS when
                the Premmia GX system BIOS is configured to run in the
                multi-sector access mode.

CAUSE:          During execution of multi-sector access commands, the drive
                issues one interrupt per sector.  However, the ANSI (American
                National Standards Institute) ATA Attachment Interface
                Specification requires one interrupt per multi-sector block.
                The Premmia GX system BIOS requires compliance with the ATA
                specification.  With one interrupt per sector, a data underrun
                occurs leading to the boot failure.

SYSTEMS
AFFECTED:           AST
                PART NUMBER       DESCRIPTION                        REVISION

                501547-XXX      PREMMIA GX P/90                        All
                501522-XXX      PREMMIA GX                             All


SOLUTION:       1. Model CP30544 is no longer manufactured.  The drives which
                   replace this model do not have this problem.  The
                   replacement drives are CFA540A and CFS540A.

                2. Conner provides a work-around which requires that interrupt
                   staging be disabled.
                   Conner has a utility that will reconfigure the drive to
                   disable staging.  This utility is in the FEATURE.ZIP file
                   on Conner's bulletin board.  Download this file by dialing
                   (408) 456-4415.  Unzip the file and follow the README.DOC
                   file's instructions.