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Power Hardware

Whither Moore's Law; Introducing Koomey's Law 105

Joining the ranks of accepted submitters, Beorytis writes "MIT Technology review reports on a recent paper by Stanford professor Dr. Jon Koomey, which claims to show that the energy efficiency of computing doubles every 1.5 years. Note that efficiency is considered in terms of a fixed computing load, a point soon to be lost on the mainstream press. Also interesting is a graph in a related blog post that really highlights the meaning of the 'fixed computing load' assumption by plotting computations per kWh vs. time. An early hobbyist computer, the Altair 8800 sits right near the Cray-1 supercomputer of the same era."
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Whither Moore's Law; Introducing Koomey's Law

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  • Power Hog (Score:5, Interesting)

    by Waffle Iron ( 339739 ) on Tuesday September 13, 2011 @06:23PM (#37392450)

    My favorite example of computing (in)efficiency is the USAF's SAGE bomber tracking computers introduced in the 1950s. These vacuum tube machines had CPU horsepower probably in the same ballpark as an 80286, but could draw more than 2 megawatts of power each. They didn't decommission the last one until the 1980s.

  • True, but... (Score:5, Interesting)

    by PaulBu ( 473180 ) on Tuesday September 13, 2011 @06:50PM (#37392654) Homepage

    I do not think that you get net energy savings (by using the same basic technology, e.g., CMOS at room temeprature or "cold"), if you take into account the fact that cooling things down also costs energy! For example, liquid helium refrigeration costs about 1 kW of wall outlet power to compensate for 1 W dissipated at 4.2 K.

    Changing your basic technology to, e.g., some version of superconductor-based logic can help (a lot!), current state of the art (in my very biased opinion, since I am cheering for those guys, and have been involved in related research for years) is here: [] ...

    Paul B.

  • Re:Power Hog (Score:5, Interesting)

    by anubi ( 640541 ) on Tuesday September 13, 2011 @07:16PM (#37392862) Journal
    Even the idea one could even implement a vacuum-tube machine capable of performing at 286-levels to me is a miracle in itself. 6502 maybe, but, to me, even the lowly 286 represents a level of sophistication I could not even imagine being implemented with vacuum-tube technology.

    I've never seen a SAGE, but it must have been quite a machine. In my imagination, it must have been about the size of a Wal-Mart. With the physical size of the thing, it would amaze me that they would be able to clock the thing anything more than 100 KHz or so.

    Yes, I do know what a 6SN7 is. And a 12AT7, which I suspect the machine was full of ( or its JAN equivalent).

    Do the designations 12SA7, 12SK7, 12SQ7, 50L6, 35Z5 still ring a bell with anyone?

God doesn't play dice. -- Albert Einstein