Jacob R. Lorch and Alan Jay Smith

EECS Department, University of California, Berkeley

Technical Report No. UCB/CSD-97-961

, 1997

http://www2.eecs.berkeley.edu/Pubs/TechRpts/1997/CSD-97-961.pdf

The utility of a portable computer is critically dependent on the period it can be used while running off the battery. In this paper, we present a study of power consumption in Apple Macintosh computers. We measure the existing power consumption for each system component using built-in measuring tools. Since total power consumption is a function of user workload, we use eight user workload traces to determine power use as observed in practice. Apple currently implements some power-saving features, and the effectiveness of those features is estimated; we find typical power savings of 41-66%. After the use of basic power-saving techniques, we find that the major power users are the backlight (25-26%), the CPU (9-25%), the display (4-17%), the video circuitry (6-10%), and the hard drive (4-9%). We then evaluate possible changes in system hardware and software with regard to the power savings they might offer.

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BibTeX citation:

@techreport{Lorch:CSD-97-961,
    Author= {Lorch, Jacob R. and Smith, Alan Jay},
    Title= {Energy Consumption of Apple Macintosh Computers},
    Year= {1997},
    Month= {Jun},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/1997/5500.html},
    Number= {UCB/CSD-97-961},
    Abstract= {The utility of a portable computer is critically dependent on the period it can be used while running off the battery.  In this paper, we present a study of power consumption in Apple Macintosh computers. We measure the existing power consumption for each system component using built-in measuring tools.  Since total power consumption is a function of user workload, we use eight user workload traces to determine power use as observed in practice.  Apple currently implements some power-saving features, and the effectiveness of those features is estimated; we find typical power savings of 41-66%. After the use of basic power-saving techniques, we find that the major power users are the backlight (25-26%), the CPU (9-25%), the display (4-17%), the video circuitry (6-10%), and the hard drive (4-9%). We then evaluate possible changes in system hardware and software with regard to the power savings they might offer.},
}

EndNote citation:

%0 Report
%A Lorch, Jacob R. 
%A Smith, Alan Jay 
%T Energy Consumption of Apple Macintosh Computers
%I EECS Department, University of California, Berkeley
%D 1997
%@ UCB/CSD-97-961
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/1997/5500.html
%F Lorch:CSD-97-961