Chess Champion Mark IV
Chess Champion Mark IV, (Chess Champion Super System Mark IV)
a dedicated chess computer manufactured and released by SciSys in 1981 as successor of the Chess Champion Super System III. The computer had a 6502 CPU @ 2MHz with a 12 KiB Philidor Software program written by Mike Johnson, and was superseded by the Chess Champion Mark V later in 81  . Chess Champion Mark IV participated at the CPWTIPC 1981, where it lost the last round by default because the computer was stolen after round 6  .
- Chess Champion Super System IV from Chess Computer UK by Mike Watters
- SciSys Chess Champion Super System MK IV from Schachcomputer.info Wiki