That do something on short or no power systems. Ready?

1. https://www.google.com/search?q=Dell+hold+down+the+d+key&

2. The old remove the battery and charger reset the bios settings method. VARIES with models but for years I've brought back a few machines by removing the battery (big one) and unplugging the charger (which we do first.) Now with those out I hold the power button for 60 seconds. Release, slip in the big battery and apply power. Test and see what happens.