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Despite there is no risk for HW, it's quite uncomfortable for who works on them.
I noticed that if I connect my MBP to an external display when it runs with battery, it does not get (so) hot.
I suppose that the MBP uses another configuration of its graphics framework when it is not connected to power adapter. Therefore, I hypothesize that if it used the same graphics configuration when it's plugged to the power, then the overheating would be reduced.
Is there a way to make the MPB use the same graphics configuration for external displays also when it is connected to the power?