The ATI Displays tab provides control over multiple-monitor features. Here you can enable/disable display devices and swap the assignment of Primary and Secondary displays.
The ATI Displays Tab
ATI Displays Tab
Scheme
Displays the drop-down list of available display-device configurations that have previously been created. New configurations can be entered here and then saved using the Save button.
Hotkey
Associates a hotkey with a scheme. To input the hotkey, highlight the field and press the appropriate key combination on your keyboard.
Save button
Saves display-device configuration schemes.
Delete button
Deletes display-device configuration schemes.
Display buttons
Enables or disables a display device; they also indicate whether a device is enabled or disabled.
Troubleshoot button
Opens a Troubleshoot dialog to assist with possible display problems.
To enable or disable a display
If the enable/disable button is green, it indicates the device is enabled. If it is red, it indicates the device is disabled. If the button is greyed out, the device is not an option. For example, if there is only one monitor connected, all buttons will be grey.
Click the enable/disable button for the display device you want to enable/disable.
Click OK or Apply to save the changes.
Note: Due to power restrictions, you can normally only have two devices active at the same time; for example, two monitors or a monitor and a TV.
To save a display-device scheme
Display-device selections can be saved as a scheme for quick recall.
Click the enable/disable button for the display devices you want to have active.
Type a name into the Scheme drop-down list field.
Click Save to save the scheme.
Dynamic Display Reassignment
You can change the assignment of your Primary and Secondary display on the fly, without rebooting.
Note: Before you can change the assignment of the Primary display, at least one Secondary display and the Extended Desktop mode must be enabled. Extended Desktop mode is enabled through the Windows® Display Property dialog, under Settings. For more information, consult your Windows® documentation.
To assign your Primary monitor
Click the buttons to assign the Primary monitor:
For Windows® XP
The ATI Displays tab shows you the display(s) that are active. The Primary display has the button depressed. To change the display assignment, click the Primary display's button or click the button of the other display device.
For Windows® 2000
Clicking the button will reassign the Primary and Secondary monitors. Clicking the button creates a clone or mirror image of the Primary display onto the Secondary display. Clicking the button extends your desktop to a Secondary display located to the right of the Primary display. Clicking the button extends your desktop to a Secondary display located below the Primary display.
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for the display device you want to enable/disable. 
for the display devices you want to have active. 
button depressed. To change the display assignment, click the Primary display's 
button or click the 
button of the other display device.
button will reassign the Primary and Secondary monitors. Clicking the 
button creates a clone or mirror image of the Primary display onto the Secondary display. Clicking the 
button extends your desktop to a Secondary display located to the right of the Primary display. Clicking the 
button extends your desktop to a Secondary display located below the Primary display.