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Q74764: Cannot Run Windows Because of Video Device Conflict

Article: Q74764
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:3.0,3.0a
Operating System(s): 
Keyword(s): 
Last Modified: 08-OCT-1999

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The information in this article applies to:

- Microsoft Windows versions 3.0, 3.0a 
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SUMMARY
=======

When video memory has been used by another application or device driver,
Microsoft Windows 3.0 doesn't start and displays the following message:

  Cannot run Windows because of video device conflict;
  Run setup again

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

It is possible to use certain areas of the upper memory area (UMA) to load
device drivers high on 386 based machines. This can be done with MS-DOS version
5.0 and later, QEMM, 386MAX, and other third-party device drivers.

If a range needed for Windows graphical display is used, this error occurs. For
example, a standard VGA setup requires memory ranges A000-AFFF and B800- BFFF.
On some graphic adapters, the range A000-C7FF may be used.

This error occurs regardless of any EMMEXCLUDE statement in the SYSTEM.INI file.

Before attempting to use video memory ranges, be sure to create a MS-DOS bootable
system disk.

For Microsoft MS-DOS version 5.0 and later, be sure not to use any video memory
area necessary to run Windows. By default, EMM386.EXE does not use the range
A000-BFFF. It is possible to include these memory ranges; be sure to test for
compatibility when attempting to use these ranges. It may be necessary to
exclude the range C000-C7FF on some video adapters by editing the CONFIG.SYS
file and changing the EMM386.EXE line as follows:

       DEVICE=C:\DOS\EMM386.EXE NOEMS X=A000-C7FF

On VGA displays, it is frequently possible to use the range B000-B7FF. To test
this configuration on your 386, change the EMM386.EXE line as follows:

       DEVICE=C:\DOS\EMM386.EXE NOEMS X=A000-AFFF I=B000-B7FF X=B800-BFFF

Additional query words: 3.00 3.00a 3.0a 3.0 3rdparty win30

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Keywords          :  
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin300 kbWin300a
Version           : WINDOWS:3.0,3.0a

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