My name is Nischith and I work for the Social Media and Community Team at Dell.
Connect your Laptop to an External Monitor, once it's connected Hold down FN and Press F8 (Dell System) this should switch the display to the screen on the External Monitor.
You can connect your system to external monitor through DVI, VGA or HDMI port (Depends on the port available on your laptop)
For Display Ports images, Click on the link below
If the screen looks fine on the external monitor then your system needs LCD replacement.
Social Media Responder