Troubleshooting Multiple Displays
The default refresh frequency setting is typically around 60Hz or 70 Hz, although your monitors may support a higher setting. A higher refresh frequency can reduce flicker, but a setting that is too high can make the display unusable, and may even damage the hardware.
If the refresh frequency is higher than 60Hz and the monitor display goes black when Windows XP is started, restart the system in Safe Mode and change the refresh frequency for all monitors to 60Hz. It may be necessary to double-check this setting in the Unattended Installation script file, normally called unattend.txt.
Multiple displays can cause problems with some older applications, particularly DOS applications. If a DOS application causes both of your screens to flicker and then go completely dark, you may have to adjust the display settings so that your application runs and is viewable on both monitors.
You can do this by restarting the system and selecting Safe Mode at the F8 startup menu. Once you can see the contents of your desktop, you can configure the DOS application to run in a window and change the Display settings from Default to Optimal.
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