[comp.sys.ibm.pc] MS Windows 286 and Extended/Expanded Memory

skl@van-bc.UUCP (Samuel Lam) (05/22/89)

Could somebody tell me if MicroSoft Windows 286 on an AT can make
direct use of any AT extended or LIM expaned memory.

Thanks in advance.

-- 
Samuel Lam     {alberta,watmath,uw-beaver,cs.ubc.ca}!ubc-cs!van-bc!skl

bturner@hpcvlx.HP.COM (Bill Turner) (05/23/89)

> Could somebody tell me if MicroSoft Windows 286 on an AT can make
> direct use of any AT extended or LIM expaned memory.

Sort of....  I don't think it can take advantage of extended (protect-mode)
memory, but it can use LIM 4.0 memory to its advantage.

To do this, you need to:

   1) Lobotomize your system so that it supplies 256K of conventional
      memory.

   2) Set up your LIM 4.0 board to backfill the remaining 384K from EMS.

   3) Make sure the device driver is configured to allow mappable conventional
      memory (MC option for EMM.SYS from Intel).

Now, each Windows application will be run in its own bank of memory, giving
the appearance that there is more memory available than 640K.  You can
still get out of memory errors (especially if there's a lot of SHARED memory
allocated), but in general each app has more space in which to run, causing
less disk access.

CAVEAT:  It's Monday morning, and I may be wrong on some of the information,
but this worked for me...

--Bill Turner (bturner@hp-pcd.hp.com)
HP Corvallis Information Systems