I'm configuring a new MacBook Pro 15″ 2015 and wanted to know if the processor speed affects the battery life?
- 2.5GHz Quad-core Intel Core i7, Turbo Boost up to 3.7GHz
- 2.8GHz Quad-core Intel Core i7, Turbo Boost up to 4.0GHz
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Sign up to join this communityI'm configuring a new MacBook Pro 15″ 2015 and wanted to know if the processor speed affects the battery life?
You want to know the 'performance per watt'. In computing, performance per watt is a measure of the energy efficiency of a particular computer architecture or computer hardware. Literally, it measures the rate of computation that can be delivered by a computer for every watt of power consumed.
2.5GHz Quad-core Intel Core i7 = 21.05 pt/W
2.8GHz Quad-core Intel Core i7 = 33.4 pt/W
So, when only looking at the 'performance per watt' you would be better of with the 2.8GHz
Sources used: Wikipedia, cpuboss.com - 2.5GHz, cpuboss.com - 2.8GHz
note: not 100% sure if I picked the correct processor types.
Considering two CPUs of the same generation (i.e. same die manufacturing process), I would expect the higher clock rate to induce some -perhaps small- increase in power consumption, as noted by CousinCocaine. This need not affect battery life directly, however:
Basically, what it boils down to is that modern laptops have huge batteries occupying a large proportion of the case. This results in longer battery charge duration, but reduces airflow.
Now, I do not have any actual numbers on battery life in similar laptops with different CPUs, so other factors may also be as important.