I have a MacBook air that was purchased for my daughter for college in August 2017. Recently she did an update and since then it will turn on and we here the chime but the screen stays completely black. I have tried various steps such as hift+Control+Option+Power button at the same time for a few seconds as well as holding the "s" while powering and other options starting with the "P" and "R" and still nothing. I have checked and sometimes the caps lock button light turns on, other times during reboots it doesn't. I can't figure out what is going on but I didn't have the money for apple care, the store says I have to send it out for repair but for $500 and I am barely putting a roof over my kid's heads with a current layoff at work. Anyone know what the problem might be for me to try at home?