What do you mean "over-heating". Do you go around putting your hand on your audio receiver or TV to check how hot the insides get? Keep your hand off it.
As in my MacBook never got hot with 12 hours of use, yet 1 hour of use with the new iMac and the top left back is very hot... I'm just asking if its something I should be concerned with...
I like bobtomay's analogy, it's a good one. No - you don't need to be concerned unless your iMac is shutting down or you're experiencing some other performance symptom. This iMac is much more powerful than your MacBook which of course, will generate more heat.
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