
INTEL CORPORATION

CLASSIC R

Processor         80486SX/80486DX/80486DX2
Processor Speed   25/33/50(internal)/66(internal)MHz
Chip Set          VLSI
Max. Onboard DRAM 32MB
Cache             64/128/256KB
BIOS              Phoenix
Dimensions        330mm x 218mm
I/O Options       Floppy drive interface, IDE interface, parallel port,
                  PS/2 mouse port, serial ports (2), VESA feature
                  connector, VGA port, riser slot
NPU Options       None

[Image]

                                CONNECTIONS

  Purpose                   Location   Purpose                   Location

  VGA port                    J1       Chassis fan power           J26

  Parallel port               J2       IDE interface LED           J29

  Serial port 2               J3       Power LED & keylock         J30

  Serial port 1               J4       Reset switch                J31

  PS/2 mouse port             J5       Chassis fan power           J32

  VESA feature connector      J10      Speaker                     J33

  IDE interface               J14      Riser slot                  SL1

  Floppy drive interface      J15

                        USER CONFIGURABLE SETTINGS

                Function                    Jumper           Position

     12v to flash BIOS enabled               J12           pins 1 & 2
                                                              closed

      12v to flash BIOS disabled              J12           pins 2 & 3
                                                              closed

     Flash BIOS recovery mode                J13           pins 1 & 2
      disabled                                                closed

      Flash BIOS recovery mode enabled        J13           pins 2 & 3
                                                              closed

     On board video enabled                  J16           pins 1 & 2
                                                              closed

      On board video disabled                 J16           pins 2 & 3
                                                              closed

     Floppy drive write protect              J17           pins 2 & 3
      enabled                                                 closed

      Floppy drive write protect              J17           pins 1 & 2
      disabled                                                closed

     Password enabled                        J20           pins 2 & 3
                                                              closed

      Password clear                          J20           pins 1 & 2
                                                              closed

     CMOS access enabled                     J21           pins 1 & 2
                                                              closed

      CMOS access disabled                    J21           pins 2 & 3
                                                              closed

     CMOS memory normal operation            J28             Closed

      CMOS memory clear                       J28              Open

  Note: The location of the above jumpers are unidentified.

                DRAM CONFIGURATION

      Size            Bank 0           Bank 1

       2MB        (1) 512K x 36         NONE

       4MB        (1) 512K x 36    (1) 512K x 36

       4MB         (1) 1M x 36          NONE

       6MB        (1) 512K x 36     (1) 1M x 36

       6MB         (1) 1M x 36     (1) 512K x 36

       8MB         (1) 1M x 36      (1) 1M x 36

       8MB         (1) 2M x 36          NONE

      10MB        (1) 512K x 36     (1) 2M x 36

      10MB         (1) 2M x 36     (1) 512K x 36

      12MB         (1) 1M x 36      (1) 2M x 36

      12MB         (1) 2M x 36      (1) 1M x 36

      16MB         (1) 2M x 36      (1) 2M x 36

      16MB         (1) 4M x 36          NONE

      18MB        (1) 512K x 36     (1) 4M x 36

      18MB         (1) 4M x 36     (1) 512K x 36

      20MB         (1) 1M x 36      (1) 4M x 36

      20MB         (1) 4M x 36      (1) 1M x 36

      24MB         (1) 2M x 36      (1) 4M x 36

      24MB         (1) 4M x 36      (1) 2M x 36

      32MB         (1) 4M x 36      (1) 4M x 36

                       CACHE CONFIGURATION

      Size            Bank 0          Bank 1            TAG

      64KB          (4) 8K x 8      (4) 8K x 8       (1) 8K x 8

      128KB        (4) 32K x 8         NONE          (1) 8K x 8

      256KB        (4) 32K x 8      (4) 32K x 8     (1) 32K x 8

  Note: The orientation of Banks 0 & 1 and TAG is unidentified.

                        CACHE JUMPER CONFIGURATION

     Size       J11 pins 1 &  J11 pins 3 &   J11 pins 5 &    J11 pins 7 &
                     2             4              6               8

     64KB          Open           Open           Open           Open

    128KB         Closed          Open          Closed          Open

    256KB         Closed         Closed          Open          Closed

  Note: The location of J11 is unidentified.

                          CPU TYPE CONFIGURATION

      Type           J22            J23           j24            j25

     80486SX      pins 2 & 3     pins 1 & 2    pins 1 & 2     pins 1 & 2
     (PQFP)         closed        closed         closed         closed

     80486SX      pins 1 & 2     pins 2 & 3    pins 2 & 3     pins 2 & 3
     (PGA)          closed        closed         closed         closed

    80486DX       pins 2 & 3     pins 1 & 2    pins 1 & 2     pins 1 & 2
                    closed        closed         closed         closed

    80486DX2      pins 2 & 3     pins 1 & 2    pins 1 & 2     pins 1 & 2
                    closed        closed         closed         closed

            Note: The locations of J22, J23, J24 & J25 are unidentified.
            The location of the PQFP socket is unidentified.

                   CPU SPEED CONFIGURATION

        Speed                J18                  J19

        25MHz          pins 1 & 2 closed   pins 1 & 2 closed

        33MHz          pins 1 & 2 closed   pins 2 & 3 closed

       50iMHz          pins 1 & 2 closed   pins 1 & 2 closed

       66iMHz          pins 1 & 2 closed   pins 2 & 3 closed

  Note: The locations of J18 & J19 are unidentified.

                            VRAM CONFIGURATION

          Size                    Bank 0                   Bank 1

          512KB                   512KB                     NONE

           1MB                    512KB                 (4) 256K x 4

  Note: Bank 0 is factory installed and is not configurable. The location
  is unidentified.

