[W/K] :: clock rate

  clock rate
       
           The fundamental rate in cycles per
          second at which a computer performs its most basic operations
          such as adding two numbers or transfering a value from one
          register to another.
       
          The clock rate of a computer is normally determined by the
          frequency of a crystal.  The original IBM PC, circa 1981,
          had a clock rate of 4.77 MHz (almost five million
          cycles/second).  As of 1995, Intel's Pentium chip runs at
          100 MHz (100 million cycles/second).  The clock rate of a
          computer is only useful for providing comparisons between
          computer chips in the same processor family.  An IBM PC with
          an Intel 486 CPU running at 50 MHz will be about twice as
          fast as one with the same CPU, memory and display running at
          25 MHz.  However, there are many other factors to consider
          when comparing different computers.  Clock rate should not be
          used when comparing different computers or different processor
          families.  Rather, some benchmark should be used.  Clock
          rate can be very misleading, since the amount of work
          different computer chips can do in one cycle varies.  For
          example, RISC CPUs tend to have simpler instructions than
          CISC CPUs (but higher clock rates) and pipelined
          processors execute more than one instruction per cycle.
       
          (1995-01-12)