When I try to boot my Mac I get nothing but strange beeps. They beep as follows:
BEEP BEEP BEEP [3 second pause] BEEP BEEP BEEP [3 second pause] and it continues until I power off.
So far, I have:
- checked with Apple KB - About Mac startup tones and this pattern is not listed as an official form of communication.
- rebooted a number of times and the same exact pattern occurs.
- used a timer to verify it is definitely 3 seconds in between the 3 beeps.
- booted into Apple Hardware Test and no problems found after running extended tests
Is my Mac possessed? Assuming not, what is it trying to tell me?
For various reasons I want to re-install the original Mac OS X. To do this I am trying to boot from an original Snow Leopard disc in the SuperDrive. I have no reason to suspect a problem with either the disc (no scratches or other signs of damage and it boots a Mid 2009 MacBook Pro just fine) or the optical drive (it loads other discs fine).
The Mac boots fine otherwise (both normally and in Safe Mode), but just doesn’t want to boot from this disc and I have no idea why, but I’m pretty sure the beeps are the key! :)
- iMac, 27", Mid 2011
- 16GB RAM
- 2 GB GDDR5 (Radeon HD 6970M)
- 3.4GHz Intel Core i7
- Mac OS X El Capitan 10.11.6 installed on the internal drive