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AST RESEARCH, INC.          TECHNICAL BULLETIN # 0973              9-16-94

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                          ASCENTIA 900N DRIVE CAPACITY


PROBLEM:        The Ascentia 900N system with a 340 MB hard drive displays
                confusing memory capacities.  A 340MB hard drive only shows
                325MB of disk space.  The FDISK utility only sees 325MB when
                it should be reporting 340MB.

CAUSE:          There are two ways the industry refers to "Megabyte" when
                refering to drive capacity.  The first is used by typical
                drive manufacturers and is calculated as 1 X 10^6 (1,000,000
                bytes).  The second (which is "real" capacity is known as
                1024^2 (1024 * 1024).  The second is actually 1,048,576 bytes
                while the first is 1,000,000 bytes - a difference of 48,576
                bytes.  This discrepancy occurs for each megabyte of stated
                drive capacity 340 * 48,576 in this instance - or 16,515,840
                bytes.

SYSTEMS
AFFECTED:           AST
                PART NUMBER         DESCRIPTION

                501300-301      ASCENTIA 900N 4/50 COLORPLUS-9

SOLUTION:       There is actually no problem.  The drive has the correct
                amount of bytes as stated.  It is only a matter of
                interpretation.

                FDISK is reporting 325 * 1,048,576 = 340,787,200 bytes.
                Likewise, a 500 Megabyte Drive actually contains 500 *
                1,048,576 = 524,288,000 bytes.

                CHKDSK shows a slightly larger size.  CHKDSK makes an attempt
                to CALCULATE the actual number of bytes by multiplying Heads *
                Sectors per Track * Number of cylinders * 512 bytes per sector.