Dell 14R- No display at all (not even on external monitor), 8 beep pattern. only fan sound and beep

hi

I have issue with my inspiron 14R. On switching power on, it beeps 8 times-stop-beep 8 times. there is no display on screen (its black totally). No booting. Only sound of fan. I have tried to connect to external monitor but found no display. Please suggest.

Thanks