Windows with Hercules and a Secondary Display Connected (44111)


The information in this article applies to:

  • Microsoft Windows 3.0
  • Microsoft Windows 3.0a
This article was previously published under Q44111

SUMMARY

There is no method of running Microsoft Windows installed for Hercules if a secondary display adapter is present in the system. This limitation exists because Windows uses the second video page of the Hercules display card for its own function. This area of memory is also used by color (CGA/EGA/VGA) displays; therefore, a conflict results, causing erroneous output to both displays.

MORE INFORMATION

The reason you can run on a color adapter with a Hercules card installed in addition to the color adapter is because the first video page of the Hercules display card is the default and does not conflict with another display type in memory.

If you write to the standard color adapter area of memory, you are not writing to the first page; thus, no output or conflict occurs with the Hercules display. This means that the only way to run correctly on a Hercules adapter is to have only the single display card in the system.
Modification Type:MinorLast Reviewed:7/7/2005
Keywords:KB44111
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