MS-DOS
Don – The '386 does have its good points! Even with today's version of
AutoCAD (and other software) designed for the 8088, 8086, or 80287, the '386
really flings those bits around. One thing to keep in mind is that both the
'286 and the '386 support extended memory, which will make it possible to run
programs larger than 640K on OS/2. While extended memory is useful on DOS
for storing large amounts of data, as in AutoCAD's paging area, programs
can't execute from it without additional OS support. LIM Expanded memory,
basically, is a kludge to allow CPUs without protected mode (8088, 8086) to
access more data. To use extended memory, the CPU must be switched to
protected mode; the '386 has an efficient way to switch back to real mode,
the '286 does not and must be reset to get out of protected mode. Using one
of the "DOS extender" packages, it may be possible to utilize extended memory
on a '286 or '386 for program code AND data, and we're looking into this
along with numerous other options. Stay tuned.
.