
DELL COMPUTER CORPORATION

DIMENSION 486SX/25, 486DX/33, 486DX2/50

Processor            80486SX/80487SX/80486DX/80486DX2
Processor Speed      25/33/50(internal)/50/66(internal)
Chip Set             OPTI
Max. Onboard DRAM    64MB
SRAM Cache           64/256KB (optional module)
BIOS                 AMI
Dimensions           330mm x 218mm
I/O Options          Floppy drive interface, IDE interface, bus mouse port

                     parallel port, serial port (2), VGA port
NPU Options          None

[Image]

                                CONNECTIONS

  Purpose                   Location   Purpose                   Location

  PS/2 mouse                  J1       IDE interface LED           J23

  IDE interface               J5       Reset switch                J24

  Floppy drive interface      J6       Speaker                     J25

  Parallel port               J8       Power LED & keylock         J26

  Serial port (COM B)         J9       VGA port                    J27

  Serial port (COM A)         J10

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Monitor type select color                W1            pins 1 & 2
                                                              closed

      Monitor type select monochrome           W1            pins 2 & 3
                                                              closed

     CMOS memory normal operation             W2            pins 1 & 2
                                                              closed

      CMOS memory clear                        W2            pins 2 & 3
                                                              closed

     I/O bus speed select SYSCLK/2            W3            pins 2 & 3
                                                              closed

      I/O bus speed select SYSCLK/1            W3            pins 1 & 2
                                                              closed

     On-board VGA enabled                     W10           pins 1 & 2
                                                              closed

      On-board VGA disabled                    W10           pins 2 & 3
                                                              closed

                            DRAM CONFIGURATION

     Size         Bank 0         Bank 1         Bank 2         Bank 3

     1MB         (1) 256K x       NONE           NONE           NONE
                    36

     2MB         (1) 256K x    (1) 256K x        NONE           NONE
                    36             36

     3MB         (1) 256K x    (1) 256K x     (1) 256K x        NONE
                    36             36             36

     4MB         (1) 256K x    (1) 256K x     (1) 256K x    (1) 256K x 36
                    36             36             36

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

     5MB        (1) 1M x 36    (1) 256K x        NONE           NONE
                                   36

     6MB        (1) 1M x 36    (1) 256K x     (1) 256K x        NONE
                                   36             36

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

     9MB        (1) 1M x 36   (1) 1M x 36     (1) 256K x        NONE
                                                  36

     10MB       (1) 1M x 36   (1) 1M x 36     (1) 256K x    (1) 256K x 36
                                                  36

     12MB       (1) 1M x 36   (1) 1M x 36    (1) 1M x 36        NONE

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

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

     17MB       (1) 4M x 36    (1) 256K x        NONE           NONE
                                   36

     18MB       (1) 4M x 36    (1) 256K x     (1) 256K x        NONE
                                   36             36

     20MB       (1) 4M x 36   (1) 1M x 36        NONE           NONE

     24MB       (1) 4M x 36   (1) 1M x 36    (1) 1M x 36        NONE

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

     33MB       (1) 4M x 36   (1) 4M x 36     (1) 256K x        NONE
                                                  36

     34MB       (1) 4M x 36   (1) 4M x 36     (1) 256K x    (1) 256K x 36
                                                  36

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

     40MB       (1) 4M x 36   (1) 4M x 36    (1) 1M x 36     (1) 1M x 36

     48MB       (1) 4M x 36   (1) 4M x 36    (1) 4M x 36        NONE

     64MB       (1) 4M x 36   (1) 4M x 36    (1) 4M x 36     (1) 4M x 36

                          CPU TYPE CONFIGURATION

        CPU            Jumper W6          Jumper W7         Jumper W8

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

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

      80487SX          pins 1 & 2         pins 1 & 2        pins 1 & 2
                         closed            closed             closed

      80486SX          pins 2 & 3         pins 2 & 3           open
                         closed            closed

                         SRAM JUMPER CONFIGURATION

      Size            Jumper W4         Jumper W5           Jumper W9

      64KB            pins 2 & 3        pins 2 & 3      pins 2 & 3 closed
                       closed             closed

      256KB           pins 1 & 2        pins 1 & 2      pins 1 & 2 closed
                       closed             closed

                     VIDEO SWITCH CONFIGURATION (SW1)

         Mode           switch     switch    switch    switch    switch 5
                          1          2         3         4

     56Hz vertical       open      open       N/A       N/A        N/A
       refresh

     60Hz vertical       open     closed      N/A       N/A        N/A
       refresh

     72Hz vertical      closed     open       N/A       N/A        N/A
       refresh

  Enable interlaced      N/A        N/A       open      open       N/A

  60Hz non-interlaced    N/A        N/A       open     closed      N/A

  72Hz non-interlaced    N/A        N/A      closed     open       N/A

  31.5KHz horizontal     N/A        N/A       N/A       N/A        open
      scan rate

   40KHz horizontal      N/A        N/A       N/A       N/A       closed
      scan rate

              VRAM CONFIGURATION

      Size           VRAM        SW1/switch 6

     512KB        (2) 256K x 4      closed

      1MB         (4) 256K x 4       open

