Path: utzoo!attcan!lsuc!maccs!cs4g6ag
From: cs4g6ag@maccs.dcss.mcmaster.ca (Stephen M. Dunn)
Newsgroups: comp.sys.ibm.pc
Subject: Re: What's Extented memory good for??
Keywords: extended memory help
Message-ID: <2517A9E4.27876@maccs.dcss.mcmaster.ca>
Date: 20 Sep 89 15:16:52 GMT
References: <1989Sep18.165750.11540@ccu.umanitoba.ca>
Reply-To: cs4g6ag@maccs.dcss.mcmaster.ca (Stephen M. Dunn)
Organization: McMaster University, Hamilton, Ontario
Lines: 57

umhudso7@ccu.umanitoba.ca () writes:
$  I have a Wells American Compustar with 2 MB, most of which is called
$EXTENDED memory, so I'm told, and that it can't really be used as is.
$THEY say that it must be used only by specialized programs or with 
$LIM emulation software.  What I really want to do is use that EXTENDED
$memory as CONVENTIONAL memory.

   If you already have 640K of conventional memory, that's it.  Anything in
excess must be used as either extended or as expanded memory (with a very
few exceptions).  You can use extended memory to emulate expanded with such
programs as PC Magazine's EMS40.SYS; however, this eats up about 70K of
conventional memory and is exceptionally slow.

   If you have a 386-based machine, you can use two programs which come with
DOS 4 that utilize the memory-mapping capabilities of the 386 to make the
extra memory behave as if it was expanded without losing either the space
in your conventional memory space or speed.

   One thing to check out, though, is your motherboard.  Many motherboards
these days allow memory in excess of 640K to be used as either extended or
as expanded memory.  Mine does; I don't know if Wells American's m/bs do.
Check out your documentation to see if there's a switch on the motherboard
that selects either extended or expanded memory.  If there is, set it to the
expanded position and add the expanded memory driver for your motherboard to
the config.sys file (if you don't have the driver, contact the retailer who
sold you the computer).

$  I'm constantly running short of memory (I'm looking at buying more,
$but it's EXPENSIVE!!) and when I check, there's all this EXTENDED
$memory just sitting there, humming to itself.  Isn't there ANY way
$(official or not) that I can _use_ this memory for everything I run
$from DOS, not just specialized programs.  I like the disk caching,
$but I'd like to put that memory to more (if not BETTER) use.

   In general, no, you can't use extended memory for too much.  Some disk-
caching programs use extended; VDISK/RAMDRIVE.SYS does, too.  OS/2 and
Windows/286 and 386 use extended memory.  Lotus 1-2-3 release 3 requires the
presence of extended memory.  Other than that, however, you aren't likely
to find many programs that will use it.

   But beware!  Even if you set it up as expanded memory, you still can't use
it with everything you run from DOS.  Access to expanded memory is not done
the same wasy as access to conventional memory!  Any program wishing to use
expanded memory must be specifically written to check for the presence of
EMS and must also know how to use it.  1-2-3, Symphony, WordPerfect 5, and
many other programs will use expanded memory if you have it.  Many other
programs, however, won't.  So don't expect all software to use any more
than 640K, even if you load your machine to the gills with memory.  Check out
the documentation on each piece of software to see if it will use EMS.  If
it doesn't say anything, it won't.


-- 
Stephen M. Dunn                         cs4g6ag@maccs.dcss.mcmaster.ca
**********************************************************************
       <std_disclaimer.h> = "\nI'm only an undergraduate!!!\n";
"VM is like an orgasm:  the less you have to fake, the better." - S.C.