Moore’s Law vs. Processor Power Efficiency

As CPU clock speeds start to level off, researchers have noticed that another power law has appeared in the electronics industry: power efficiency doubles every 18 months.

If you look at any human endeavor that enjoys the benefits of the application of tremendous amounts of determined brainpower, the metrics by which that endeavor is considered a success have a tendency to obey power laws. The periodicity of each, however, varies from field to field. See Kevin Kelly excellent research on the subject of Moore’s Law and air speed records. Processor power efficiency is the key now that portability is of the utmost importance and the rate of growth of battery storage capacity, while itself is also obeys a power law, the chemical nature of the endeavor leads to a much longer doubling time. This leads to all sorts of fun facts such as:

Imagine you’ve got a shiny computer that is identical to a Macbook Air, except that it has the energy efficiency of a machine from 20 years ago. That computer would use so much power that you’d get a mere 2.5 seconds of battery life out of the Air’s 50 watt-hour battery instead of the seven hours that the Air actually gets. That is to say, you’d need 10,000 Air batteries to run our hypothetical machine for seven hours.

Via Alexis Madrigal of the Atlantic.

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