Microsoft KB Archive/34193

IBM PC/XT Motherboard Switch Settings: Math Coprocessor PSS ID Number: Q34193 Article last modified on 09-23-1991 PSS database name: PSS

Summary:

The IBM PC/XT series of computers have switches on the motherboard to determine the system configuration. If these switches are set incorrectly, erratic errors can result.

The original IBM documentation for the switch settings listed incorrect settings for the coprocessor switch. The following are the correct settings:

Switch Block 1

---                          : 1 2 3 4 5 6 7 8 :                           :   x             : on Without math coprocessor   :                 : :                :                           :                 : off ---

---                          : 1 2 3 4 5 6 7 8 :                           :                 : on With math coprocessor      :                 : :                :                           :   x             : off --- Copyright Microsoft Corporation 1991.