Microsoft KB Archive/35676
HIMEM.SYS Hardware Support PSS ID Number: Q35676 Article last modified on 01-05-1989
The HIMEM.SYS XMS (eXtended Memory Specification) was written to work on an IBM (or 100-percent compatible) PC AT and IBM PS/2 system (with a 80286 or 80386 processor). Since this device driver must do some very hardware-specific duties (such as manipulating the A20 line), using this device driver on other systems may not work properly. Beginning with HIMEM.SYS Version 2.03, this XMS driver has code to detect and support the AT&T 6300, Hewlett-Packard 80286 and 80386 systems.
For other systems, the HIMEM.SYS source code can be modified by the computer OEM to work with its system. Contact your OEM to see if this has been done already. This solution is more likely than with many device drivers, since Microsoft distributes the source code for HIMEM.SYS at no charge.
Copyright Microsoft Corporation 1989.