> Please adjust the brightness of the LCD screen, while the computer is on (To Adjust the LCD Brightness hold the FN Key and Repeatedly Press the Up Arrow to increase the brightness or while holding the FN Key and Repeatedly Press the Down Arrow to decrease the brightness.)
>Run the Laptop Built-In Self-Test (BIST).To run the Built-In Self-Test performs the following:
§ Turn the computer off.
§ Press and hold the D key while pressing the power button. This will start the BIST.
§ The screen will display multiple flashing colors. Look for lines, distortion, or any other video issues you have observed.
§ The laptop will restart when the test is finished.
>Connect to an external monitor (if available), Once it's connected, press and hold down the FN and press F8, this should display the screen on the external monitor. When the external monitor does work it may be issues with the BIOS or Video driver or LCD screen itself. Verify that the BIOS and Video drivers are the latest available from http://www.dell.com/support/drivers/us/en/19/DriversHome/NeedProductSelection
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