Q: iMac responds to power-up with "beep-beep-beep-pause" repeat.

This indicates either bad or faulty RAM or improperly installed RAM.

Here is a list of indications for 'Beeps'

1 beep = no RAM installed
2 beeps = incompatible RAM types
3 beeps = no good banks
4 beeps = no good boot images in the boot ROM (and/or bad sys config block)
5 beeps = processor is not usable.

The above info came from an old article that is no longer archived.   See ...

Power On Self-Test Beep Definition - Part 2

Whether it could still be regarded as valid, I don't know.

http://support.apple.com/kb/HT2538 is more recent

andyBall_uk wrote:

 

http://support.apple.com/kb/HT2538 is more recent

So iMacs no longer beep?  They tone now?   I gather I'm reading that Article correctly.

Yes, it is perhaps fortunate that Apple aren't responsible for Acceleratii incredibus.

The beeps indicated what I had stated, earlier...bad, corrupt or improperly installed RAM!

Why did everyone else chime in on this post???

?...

To link Knowledge Post Articles as confirmation.  Now that iMacs no longer beep. Users here do it all the time especially the old timers me included.  Don't take offense.

P.S.  A lot of folks like to print out KB Articles of interest to keep as reference files/notes.  I got a note book full of them.