Won't turn on after being on sleep.
Im having the issues with the same iMac model 24" EMC No.2134 Model A1225. It started a couple of months ago that i would put the computer on sleep and it wouldn't turn back on, unless i unplugged it for a while. Now recently it just turned off and never came back on. Im going to try replacing the power supply as well. My hint that it might be that was that i was just surfing the net and my computer just turned off. This website is amazing, ton of excellent information. Thank You!!
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