My name is Krishna and I work for the Social Media and Community Team at Dell. To makes things more clearer for you, the listings for the monitor and display adapter are separate in Device Manager.
The Inspiron N5110 supports nVidia's Optimus technology. You cannot set nvidia graphics card as the primary option, but you can control which setting Optimus will use with a particular title or application by referencing the Optimus Application Profile list within the NVIDIA Control Panel. To create a new profile for an application:
Open the NVIDIA Control Panel.
Select Manage 3D Settings.
Select Program Settings tab
Click Add button.
Browse to and select the application executable that needs the new profile.
Or choose the preferred application from the drop menu.
Select the features and settings you wish to change for this application.