I haven't been able to come across anything definitive yet on wether or not Haswell i5 vs i7 upgrade consumes more power or makes more heat. Last year there was a difference, that was tested in a real world situation. According to Intel's specs, both the i5 and i7 have the same power draw, which would lead one to believe their may not be a difference or if so almost unmeasurable. If we go based of previous chips & experience then the i5 will have better bat life & less heat than the i7. If we go based on the tech specs give by Intel the i5 & i7 will have negligible differences in battery life and heat. Anyone come across any real world tests , even if not a mac, but just the chips themselves?