Mac will not start
Make sound when pushing power button but screen stays dark
iMac, OS X 10.10
Make sound when pushing power button but screen stays dark
iMac, OS X 10.10
Then your iMac has hardware, LCD or LCD drive IC or back light, related issue.
You'd better contact Apple support or make Genius Bar reservation.
https://support.apple.com/en-us/HT201232
https://www.apple.com/retail/geniusbar/
Tried all info from apple still black screen. i can hear the motor running
Mac will not start