Q74655: Tandy 1000 TX Video Memory Uses the High Memory Area (HMA)

Article: Q74655
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:5.0,5.0a,6.0,6.2,6.21,6.22
Operating System(s): 
Keyword(s): 
Last Modified: 22-NOV-1999

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22 
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SYMPTOMS
========

When you try to load HIMEM.SYS on a Tandy 1000 TX, you receive the following
error message:

  VDISK Memory Allocator Already Installed: XMS Driver Not Installed.

CAUSE
=====

The Tandy 1000 TX, an 80286 machine, uses the high memory area (HMA) for video
memory. According to the Tandy Corporation, video memory is hard-wired to the
A20 line. As a result, HIMEM.SYS does not load.

Third-party XMS memory managers also encounter a similar message.

MORE INFORMATION
================

The Tandy 1000 TX is manufactured by Tandy Corporation, a vendor independent of
Microsoft; we make no warranty, implied or otherwise, regarding this product's
performance or reliability.

Additional query words: 6.22 5.00 5.00a 6.00 6.20 3rdparty 1000TX

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS500 kbMSDOS500a
Version           : MS-DOS:5.0,5.0a,6.0,6.2,6.21,6.22

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