
MYLEX CORPORATION

MDE486

Processor        80486SX/80487SX/80486DX/ODP486SX/80486DX2
Processor Speed  20/25/33/50(internal)/50/66(internal)MHz
Chip Set         OPTI
Max. Onboard     128MB
DRAM
Cache            64/128/256/512KB
BIOS             Mylex
Dimensions       330mm x 218mm
I/O Options      32-bit external memory card slot, floppy interface, IDE
                 interface, parallel port, serial ports (2)
NPU Options      None

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  32-bit external            CN1       Reset switch                P2
  memory card

  Serial port 1              CN2       Speaker                     P3

  Serial port 2              CN3       Power LED & keylock         P4

  Parallel port              CN4       Turbo LED                   P5

  IDE interface              CN5       IDE interface LED           P6

  Floppy drive               CN6
  interface

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Factory configured - do not alter        J11             Open

     Factory configured - do not alter        J12             Open

     Factory configured - do not alter        J20           pins 2 & 3
                                                              closed

     Factory configured - do not alter        J21           pins 1 & 2
                                                              closed

     Monitor type select color                P1             Closed

      Monitor type select monochrome           P1              Open

                            DRAM CONFIGURATION

     Size          Bank 0         Bank 1        Bank 2          Bank 3

      4MB        (4) 256K x        NONE          NONE            NONE
                     36

      8MB        (4) 256K x     (4) 256K x       NONE            NONE
                     36             36

     12MB        (4) 256K x     (4) 256K x     (4) 256K x        NONE
                     36             36            36

     16MB        (4) 256K x     (4) 256K x     (4) 256K x     (4) 256K x
                     36             36            36              36

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

     20MB       (4) 1M x 36     (4) 256K x       NONE            NONE
                                    36

     24MB       (4) 1M x 36     (4) 256K x     (4) 256K x        NONE
                                    36            36

     28MB       (4) 1M x 36     (4) 256K x     (4) 256K x     (4) 256K x
                                    36            36              36

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

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

     40MB       (4) 1M x 36    (4) 1M x 36     (4) 256K x     (4) 256K x
                                                  36              36

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

     52MB       (4) 1M x 36    (4) 1M x 36    (4) 1M x 36     (4) 256K x
                                                                  36

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

     64MB       (4) 4M x 36        NONE          NONE            NONE

     128MB      (4) 4M x 36    (4) 4M x 36       NONE            NONE

     192MB      (4) 4M x 36    (4) 4M x 36    (4) 4M x 36        NONE

     256MB      (4) 4M x 36    (4) 4M x 36    (4) 4M x 36    (4) 4M x 36

  Note:Banks 2 and 3 are used when a 32-bit external memory card is
  installed at CN1.

                            CACHE CONFIGURATION

     Size          Bank 0        Bank 1       TAG (U19)       TAG (U20)

     64KB        (4) 8K x 8     (4) 8K x 8    (1) 8K x 8        NONE

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

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

     512KB       (4) 128K x       NONE       (1) 32K x 8        NONE
                     8

                        CACHE JUMPER CONFIGURATION

  Size       J1        J2        J3       J4        J5        J6      J8

  64KB      Open      Open      Open     Open      Open      Open     2 &
                                                                      3

  128KB     Open      Open     Closed    Open     Closed     Open     1 &
                                                                      2

  256KB     Open     Closed    Closed   Closed    Closed     Open     2 &
                                                                      3

  512KB    Closed    Closed    Closed   Closed    Closed    Closed    1 &
                                                                      2

  Note: Pins designated should be in the closed position.

                          CPU TYPE CONFIGURATION

          Type                      J9                      J10

         80486SX                   Open               pins 1 & 2, 3 & 4
                                                           closed

        ODP486SX            pins 1 & 2 closed        pins 2 & 3 closed

         80487SX            pins 1 & 2 closed        pins 2 & 3 closed

         80486DX            pins 2 & 3 closed         pins 1 & 2, 3 & 4
                                                           closed

        80486DX2            pins 2 & 3 closed         pins 1 & 2, 3 & 4
                                                           closed

                          CPU SPEED CONFIGURATION

  Speed     J7      J13      J14      J15      J16      J17     J18   J19

  20MHz    Closed   Open     Open    Closed    Open    Open     1 &   1 &
                                                                2      2

  25MHz    Open    Closed   Closed    Open     Open    Open     1 &   2 &
                                                                2      3

  33MHz    Open     Open    Closed    Open    Closed   Open     1 &   2 &
                                                                2      3

  50iMHz   Open    Closed   Closed    Open     Open    Open     1 &   2 &
                                                                2      3

  50MHz    Open     Open     Open     Open    Closed   Closed   2 &   2 &
                                                                3      3

  66iMHz   Open     Open    Closed    Open    Closed   Open     1 &   2 &
                                                                2      3

  Note: Pins designated should be in the closed position.

