i487

Intel 487SX
i487

   <processor> A version of the {Intel 486DX} {microprocessor}
   with an extra pin, for use in the {coprocessor} socket of an
   {Intel 486SX} system.  The 487SX provides the {FPU} which is
   missing in the 486SX.

   Although the 486SX is completely disabled when you install a
   487SX, the 487SX design requires that you leave the 486SX in
   your PC [why?], rather than use it elsewhere.  Intel admits
   that in some systems you can unplug the 486SX and fit a 487SX
   in its place but they don't guarantee that it will always
   work.

   See {Intel 486}.

   (1995-05-10)