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Q239119: BUG: FDISK Reports Incorrect Disk Capacity for PCMCIA ATA Drives

Article: Q239119
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:95
Operating System(s): 
Keyword(s): kbOSWin95bug kbOSWin98bug kbDSupport kbGrpDSWin9xDDK
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft Windows 95 
- Microsoft Windows 98 
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SYMPTOMS
========

FDISK, when run from an MS-DOS box after Windows has been started, reports the
wrong disk size for PCCARD-based ATA drives that contain a storage capacity
greater than 1023 cylinders. This issue generally applies to disk drives that do
not appear in real mode prior to protected-mode Windows (this problem occurs,
for example, with drives where the controller has no BIOS extension, so MS-DOS
has no way of knowing that they exist).

CAUSE
=====

A bug in the IDE device driver, Esdi_506.pdr, results in FDISK using INT 13
function 8 to obtain disk geometry information. This function truncates the
cylinder count to a 10-bit value.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

Additional query words:

======================================================================
Keywords          : kbOSWin95bug kbOSWin98bug kbDSupport kbGrpDSWin9xDDK 
Technology        : kbWin95search kbWin98search kbZNotKeyword3 kbWin98
Version           : WINDOWS:95
Hardware          : x86
Issue type        : kbbug
Solution Type     : kbnofix

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