Tandy 3000 (250-4001) Math Coprocessor Faxback Doc. # 1366 Check Math Coprocessor for the correct 8MHZ 80287 Catalog number for install- ation in the Tandy 3000. There is a co-processor socket on the main logic board at location U78 on the NON-GATE ARRAY version or at location U32 on the GATE ARRAY version. All you have to do is plug the co-processor chip into the 3000 main logic board.