The Free On-line Dictionary of Computing (30 December 2018):

Pentium III
Pentium 3

    The microprocessor that was Intel Corporation's
   successor to the Pentium II, introduced in 1999 with a 500 MHz
   clock rate.  The Pentim III is very similar to the Pentium II in
   architecture.  Its external bus can be clocked at 100 or 133
   MHz, it can have up to 512 KB of secondary cache, and it
   comes in various packages including SECC2 and FC-PGA.

   The Pentium III has a P6 Dynamic Execution
   microarchitecture, a multi-transaction system bus, and MMX,
   like the Pentium II.  It adds Dual Independent Bus (DIB)
   Architecture, the Intel Processor Serial Number, Internet
   Streaming SIMD Extensions and 70 new instructions.  Some
   versions also include an Advanced Transfer Cache and Advanced
   System Buffering.

   When Intel released a 1.13 GHz version of the Pentium III
   processor using a 0.18 micron fabrication process on
   2000-07-31, it was the world's highest performance
   microprocessor for PCs.

   (http://intel.com/PentiumIII).

   (2000-10-05)