[comp.sys.ibm.pc.hardware] Windows 3, HIMEM.SYS and Extended Memory

cyang%peruvian.utah.edu@cs.utah.edu (Cheng Yang) (01/04/91)

Hi, everybody.  I have just installed Windows 3.0 on my 286 At clone and
there is a little problem with its extended memory.

I am running MS-DOS 4.01 and there are 2 MB RAM on my motherboard (above
1024 K was configured as extended memory).  In order to run Window 3.0
efficently, I put "DEVICE = C:HIMEM.SYS" in my config.sys file. and
the problem is that before I run Windows, I type "mem" to check my RAM
it reports the extended memory normally.  After I run Windows and terminate
it normally, the "mem" command reports that 0 extended memory is available.
And the DOS will not recognize the 1024 K extended memory.

However, after I remove the statement "DEVICE = C:HIMEM.SYS" from the
config.sys file, DOS will report that there are 1024 KB RAM after Windows
was run.

Is there something wrong with my system? Or is it normal?

Thank you very much for your help in advance.

*****************************************************************************
*	Ho capito, signor,si!........                                       *
*                                                                           *
*Cheng Yang				Home Address:                       *
*Department of Computer Science		808 East, 300 South, #3             *
*University of Utah			Salt Lake City, UT 84102            *
*E-Mail Address:cyang@peruvian.utah.edu	Tel: 801-322-1918                   *
*****************************************************************************

dcc@hpopd.pwd.hp.com (Daniel Creswell) (01/07/91)

Himem.sys provides access to a 64K High Memory Area (a chunk you can't usually)
get at. This is a small area of extended memory above 1Mbyte. I suspect you're
memory program can't cope with this .sys file running. Really a few more detailsare necessary. Do you run in standard,real or enhanced mode when in windows?

What else do you have in your config.sys file?

That's not much use but we could use some more data!

Regards, Dan C. (HP Pinewood UK - Big Blues Little brother!)

richardh@hpopd.pwd.hp.com (Richard Hancock) (01/07/91)

/ hpopd:comp.sys.ibm.pc.hardware / dcc@hpopd.pwd.hp.com (Daniel Creswell) / 12:29 pm  Jan  7, 1991 /

> Himem.sys provides access to a 64K High Memory Area (a chunk you can't
> usually) get at. This is a small area of extended memory above 1Mbyte.

I believe that Himem provides Windows with access to ALL extended memory by
implementing the XMS specification. (Himem only accessed the first 64K-16 bytes
- the High Memory Area - of extended memory in Windows 2.x).

Windows effectively takes-over your extended memory and provides the XMS
interface to it. It's likely that your memory checking programming doesn't talk
XMS.

Richard.