Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

My iMac beeps on startup. Does anyone know the beep codes?

I never actually knew what the beeps were, until I read "How do I reset the time on my computer without turning it on?".

share|improve this question

1 tone, a 5-second pause, repeat – No RAM installed

3 successive tones, a 5-second pause, 3 successive tones – RAM does not pass data integrity check

1 long tone when holding down the power button – Firmware upgrade in process.

3 long tones, 3 short tones, 3 long tones – Firmware restoration from CD in process.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.