Here are two methods to set up multiple monitors in Windows 7. Make sure that you connect the external monitors to your laptop or your desktop computer first.
Method 1: By keyboard shortcut "Win+P"Press the Windows logo key + P on your keyboard. Select one of the following options according to your needs: (The screen shot for this step is listed below.)
Method 2: By the "Screen Resolution" menu1. Right-click any empty area of your desktop, and then click Screen resolution. (The screen shot for this step is listed below.)
2. Click the Multiple displays drop-down list, and then select Extend these displays, or Duplicate these displays. Note If you cannot see the additional monitor(s) listed, click Detect. If does not work, try restarting your computer and do step 1 to 2 again. (The screen shot for this step is listed below.)