SMARTDRV.SYS Incompatible with Some Disk Managing Programs (78524)

The information in this article applies to:
    Microsoft MS-DOS operating system 5.0

This article was previously published under Q78524


SMARTDRV.SYS does not work with third-party disk managers that alter the disk geometry.


SMARTDRV.SYS disk caching works at the INT 13h level. To work at that level, SMARTDRV.SYS needs to know the disk's geometry (the number of heads, sectors per track, number of cylinders, and so on). SMARTDRV.SYS determines these parameters at boot time when SMARTDRV.SYS is loaded from the CONFIG.SYS file.

Some third-party disk managers alter the disk geometry to better use the hard disk. The altered geometry conflicts with SMARTDRV.SYS, which expects the original disk geometry. In addition, third-party disk managers usually assign a normal disk geometry to one portion of the hard disk and a different geometry to another portion.

SMARTDRV.SYS attempts to detect third-party disk managers. If one is detected, SMARTDRV.SYS does not run. SMARTDRV.SYS looks at the partition table in the master boot record (MBR) and looks for a known set of partition identifiers to scan for the incompatible third party disk managers.

SMARTDRV.SYS works with third-party disk managers that do not alter the geometry of the disk.

Modification Type: Major Last Reviewed: 11/26/1999
Keywords: KB78524