white screen on my dell n5110

[baddegame]

only white screen appears on my dell inspiron n5110 when started. external display comes. what would be the problem. I checked the led screen and ribbon, rams, processor all are ok. is the problem with the graphic processor. I heat the graphic processor but no answer. help me if you can.

 

[cin19]

If you had the white screen, it related to led screen, GPU, also the cable, because a white screen is the back light is on but there is no data to the display. And you did try to use the external monitor, it works fine, also you check the cable too, then means the led monitor has the problem.
Next to try to remove the battery to reset the laptop, if it still has the white screen, replace the led screen, or contact dell if the laptop is still under warranty period.