
IBM CORPORATION

PS/1 MT2133A, MT2155A, MT2168A

Processor         80486SX/80487SX/80486DX/80486DX2/P23T/P24T
Processor Speed   25/33/50(internal)/66(internal)MHz
Chip Set          Unidentified
Video Chip Set    Unidentified
Maximum Onboard   32MB
Memory
Maximum Video     1MB
Memory
Cache             64/256KB
BIOS              Unidentified
Dimensions        330mm x 218mm
I/O Options       Floppy drive interface, IDE interface, parallel port,
                  PS/2 mouse port, serial ports (2), VGA feature connector,
                  VGA port, riser slot
NPU Options       None

[Image]

                                CONNECTIONS

  Purpose                Location      Purpose                Location

  PS/2 mouse port           J2         VGA feature               J14
                                       connector

  Serial port 1             J3         Power LED             J26 pins 1 &
                                                                  2

  Serial port 2             J4         IDE interface LED     J26 pins 3 &
                                                                  4

  Parallel port             J5         Speaker                   J27

  VGA port                  J6         Power supply              J29

  Floppy drive              J7         Power supply              J30
  interface

  IDE interface             J9         Riser slot                SL1

                        USER CONFIGURABLE SETTINGS

                Function                     Label           Position

      Password normal operation               J31           Pins 2 & 3
                                                              closed

      Password clear                          J31           Pins 1 & 2
                                                              closed

                            DRAM CONFIGURATION

     Size         Bank 0         Bank 1         Bank 2         Bank 3

     2MB        (1) 512K x        None           None           None
                    36

     4MB       (1) 1M x 36        None           None           None

     4MB        (1) 512K x     (1) 512K x        None           None
                    36             36

     6MB        (1) 512K x     (1) 512K x     (1) 512K x        None
                    36             36             36

     8MB       (1) 2M x 36        None           None           None

     8MB       (1) 1M x 36    (1) 1M x 36        None           None

     8MB        (1) 512K x     (1) 512K x     (1) 512K x    (1) 512K x 36
                    36             36             36

     16MB      (1) 4M x 36        None           None           None

     16MB      (1) 2M x 36    (1) 2M x 36        None           None

     24MB      (1) 2M x 36    (1) 2M x 36    (1) 2M x 36        None

     32MB      (1) 4M x 36    (1) 4M x 36        None           None

     32MB      (1) 2M x 36    (1) 2M x 36    (1) 2M x 36     (1) 2M x 36

  Note: Banks are interchangeable.

            CACHE CONFIGURATION

     Size          Bank 0          TAG

     64KB        (8) 8K x 8    (1) 32K x 8

     256KB       (8) 32K x 8   (1) 32K x 8

                        CACHE JUMPER CONFIGURATION

    Size           J16            J17            J18             J32

    64KB        Pins 2 & 3     Pins 2 & 3     Pins 2 & 3      Pins 2 & 3
                 closed          closed         closed         closed

    256KB       Pins 1 & 2     Pins 1 & 2     Pins 1 & 2      Pins 1 & 2
                 closed          closed         closed         closed

             VIDEO MEMORY CONFIGURATION

           Size                      CN1

          512KB            512KB module installed

           1MB              1MB module installed

            CPU TYPE SELECTION

        Type                 J23

       80486SX        Pins 2 & 3 closed

       80487SX        Pins 2 & 3 closed

       80486DX        Pins 1 & 2 closed

      80486DX2        Pins 1 & 2 closed

        P23T          Pins 2 & 3 closed

        P24T          Pins 1 & 2 closed

