black screen

so randomly one day my computer wouldnt show the dell logo when it started, i tried powering up in safe mode but it didnt work, i tried to disconnect the battery and replug it but no and tried to remove the memory and reinstall it but still nothing. stangely enough that when i boot up while holding down D (RGB test) it works with no display problems. I dont know how to boot into safe mode without the screen, it just starts up with the keyboard lit up and total black screen (not lit up just completely off) so its definitely some software issue. Please help me!!!