Saturday, April 14, 2007

Multiple Display in Windows XP Professional

Using Multiple Displays:

Windows XP Professional supports multiple display configurations. Multiple displays allow you to extend your desktop across more than one monitor.


· Use of multiple displays extends the desktop across a miximum of 10 monitors
· Multiple displays must use Peripheral Component Interconnect (PCI) or Accelerated
  • Graphics Port (AGP) devices.
    · Hardware requirements for primary (main) and secondary displays differ.

    If one the display adapters are built into the motherboard, note these additional considerations:

    1. The motherboard adapter always becomes the secondary adapter. It must be multiple-display compatible.

    2. You must set up Windows XP Professional before installing another adapter. Windows XP Professional Setup disables the motherboard adapter if it detects another adapter. Some systems completely disable the onboard adapter on detecting an add-in adapter. If you are unable to override this detection in the BIOS, you cannot use the motherboard adapter with multiple displays.


    Typically, the system BIOS selects the primary display based on PCI slot order. However, on some computers, the BIOS allows the user to select the primary display device.

    You cannot stop the primary display. This is an important consideration for laptop computers with docking stations. For Example, some docking stations contain a display adapter; these often disable, or turn off, a laptop’s built-in display. Multiple display support does not function on these configurations unless you attach multiple adapters to the docking station.

    Configuring Multiple Displays:

    Before you can configure multiple displays, you must install them. When you configure multiple displays, you must configure each one in a multiple-display environment.

    To install multiple monitors, complete the following Steps:
  1. Turn off your computer and insert one or more additional PCI or AGP video adapters into available slots on your computer
  2. Plug an additional monitor into each PCI or AGP video adapter that you installed.
  3. Turn on your computer and allow windows XP Professional to detect the new adapters and install the appropriate device drivers.
  4. In Control Panel, click Appearance And Themes, and then click Display.
  5. In the Setting tab, click the monitor icon that represents the monitor you want to use in addition to your primary monitor.
  6. Select the Extend My Windows Desktop Onto This Monitor check box and then click OK.


    To configure your display in a multiple-display environment, complete the following steps:
  • In Control Panel, click Appearance And Themes, and then click Display.
  • In the Display Properties dialog box, click the Setting tab.
  • Click the monitor icon for the primary display device.
  • Select the display adapter for the secondary display, and then select the color depth and resolution.
  • Click the monitor icon for the secondary display device.
  • Select the display adapter for the secondary display, and then select the Extend My Windows Desktop Onto This Monitor check box.
  • Select the color depth and resolution for the secondary display.
  • Repeat steps 5 through 7 for each additional display.


    Windows XP Professional uses the virtual desktop concept to determine the relationship of each display. The virtual desktop uses co-ordinates to track the position of each individual display desktop.

    The co-ordinates of the top-left corner of the primary display always remain 0, 0.
    Windows XP Professional sets secondary display co-ordinates so that all the displays adjoin each other on the virtual desktop. This allows the system to maintain the illusion of a single, large desktop where users can cross from one monitor to another without losing track of the mouse.


    To change the display positions on the virtual desktop, in the Setting tab click Identify and drag the display representations to the desired position. The positions of the icons dictate the co-ordinates and the relative positions of the displays to one another.

    Troubleshooting Multiple Displays:

    If you encounter problems with multiple displays, use the troubleshooting guidelines from the below given table:

    Problem: You cannot see any output on the secondary displays

    Solution: Activate the device in the Display Properties dialog box. Confirm that you
    chose the correct video driver.

    Restart the computer to confirm that the secondary display initialized. If not, check the status of the video adapter in Device Manger.

    Switch the order of the adapters in the slots. (The primary adapter must qualify as a secondary adapter)


    Problem: The Extend My Windows Desktop Onto This Monitor check box is
    unavailable.

    Solution: Select the secondary display rather then the primary one in the Display
    prperties dialog box.

    Confirm that the secondary display adapter is supported.

    Confirm that Windows XP Professional can detect the secondary display.

    Problem: An application fails to display on the secondary display.

    Solution: Run the application on the primary display.

    Run the application in full-screen mode (Microsoft MS-DOS) or
    maximized (Microsoft Windows)

    Disable the secondary display to determine whether the problem is specific to multiple-display support.

================================================================================