I get a black screen and the start up chime that continuously loops. Keyboard commands do not work neither does putting in an os x disk as the disc drive does not seem to work either. What could be the cause of this issue? The computer has been working perfectly until now.
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iMac 27" 2010 Boot Loop Issue
- Thread starter Crispz
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Did you try SMC reset? (basically, unplug everything, particularly the power cable - but I pull all connections, to be certain that you don't get any power input from any other source. Let it sit for a couple of minutes. Plug back only power and keyboard/mouse, and try a PRAM reset (press and release the power button, and immediately hold Option-Command-P-R. You should hear the boot chime. Continue to hold the same 4 keys until you hear the boot chime two more times.
Release the keys, but hold D to go into your diagnostics test. Run both the standard and extended tests. The extended test can take quite a while if you have a lot of RAM installed.
If nothing good happens yet, or no change - try removing the RAM - all of it.
Then try to boot. You should get error beeps, because of the missing RAM. Put one pair of the sticks back in place, or maybe even just one stick, just as a test to power on for any different response.
Release the keys, but hold D to go into your diagnostics test. Run both the standard and extended tests. The extended test can take quite a while if you have a lot of RAM installed.
If nothing good happens yet, or no change - try removing the RAM - all of it.
Then try to boot. You should get error beeps, because of the missing RAM. Put one pair of the sticks back in place, or maybe even just one stick, just as a test to power on for any different response.