To use more than one display

Make sure you have securely connected the additional displays you want to use to the appropriate connections on your NVIDIA-based graphics card installed on your computer.
Verify that your displays are plugged in and turned on.
From the NVIDIA Control Panel navigation tree pane, under Display, click Set up multiple displays to open the page.

The box under Step 1 lists all the displays that are connected to your system, and shows to which GPU they are connected.
Check or clear the check boxes to select the displays that you want to use.
- In non-SLI modes, you can select up to two displays per GPU.
- In SLI mode with GeForce 8 series and later GPUs, you can select up to two displays connected to GPUs within the same SLI group. Under 4-way SLI mode, only GPUs that have two display connectors can be used to drive displays. Typically, display connectors lined up on the same slot position are connected to the same GPU.
Icons in the box under Step 2 appear, corresponding to the displays you selected.
Click Apply to activate the new display configuration.

Note: If any one of your displays isn't showing an image, make sure to repeat steps 1. and 2. If that doesn't work, restart your computer and repeat the above steps.

When a display is first activated, it is set in extended mode. Extended mode displays are identified by number in separate box icons.

In extended mode, you can click and drag the display icons to match the physical position of your displays.

To switch from extended mode to clone mode, right-click one of the display icons, then from the pop-up menu click the display that you want to be in the same Clone group, then click Apply.
Cloned displays are identified by numbers inside the same box icon.
To switch from Clone mode to extended mode, right-click the display icon box of the Clone group, click Extend, then click Apply.

To identify which display is represented by an icon, right-click the icon and then click Identify to see which display shows the same number as the icon. You can also move the mouse cursor over an icon to see more information about the display, such as manufacturer, model, connection, and resolution.