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

IBM compatible

    A computer which can use hardware and software
   designed for the IBM PC (or, less often, IBM mainframes).

   This was once a key phrase in marketing a new PC clone but
   now in 1998 is rarely used, the non-IBM wintel personal
   computer manufacturers such as Compaq, Dell and Gateway
   2000 and OS vendor Microsoft having taken control of the
   market, marginalising IBM.

   (1998-07-30)