My laptops about a year and a half old and sometimes when I open it the screen goes white and flickers like in the black and white movies. I shut the lid and then when I re-open it it's fine, still thinking it's not good though. Other than that PC works fine, although I did run a Dell Health Check that basically said PC was dying potentially but it's fine.
Welcome to the Communtiy. Please add your system model when posting on the forum. Try connecting an external monitor to the system and check if its fine on the external monitor. If it looks good on the external monitor then its an issue with your LCD. The LCD cable could be lose, you would need to reseat the cable. Contact Dell Technical Support in your region for help.