Fan sound and black screen, what should I do ?
Fan sound, Black screen, slow
shut down and disconnect all external devices
reset the smc
How to reset the System Management Controller (SMC) on your Mac - Apple Support
repeat 2 or 3 times
reset the nvram
How to reset NVRAM on your Mac - Apple Support
repeat 2 or 3 times
boot into safe mode
Use safe mode to isolate issues with your Mac - Apple Support
then reboot normally.
Fan sound and black screen, what should I do ?