Chosen Solution
The first macbook is working normally, after I plug in the external hard drive the screen suddenly died and beep beep beep continuously in the state of dead screen. Macbokk hard to restart. Until finally can live cuman continuously as it dies. What to do?
If it is 3 beeps 5sec nothing 3 beeps… The RAM is dead. if Three long tones, three short tones, three long tones: EFI ROM corruption is detected, and the computer is in EFI ROM recovery mode. Newer computers automatically recover from a corrupted ROM; when this occurs, a progress bar appears on the screen during ROM recovery mode. Don’t disturb your Mac while the ROM recovery takes place. When recovery is complete, your Mac restarts
