
EFA CORPORATION

4M50HL3

Processor        CX486SX/80486SX/CX486DX/80486DX/80486DX2/ODP486SX
Processor Speed  20/25/33/40/50(internal)/50/66(internal)MHz
Chip Set         UMC
Max. Onboard DRAM32MB
Cache            64/128/256KB
BIOS             AMI
Dimensions       330mm x 218mm
I/O Options      32-bit VESA local bus slots (3)
NPU Options      None

[Image]

                                CONNECTIONS

  Purpose                  Location     Purpose                 Location

  External battery            J1        Turbo switch              J29

  Turbo LED                   J25       32-bit VESA Local bus      S1
                                        slot

  Speaker                     J26       32-bit VESA Local bus      S2
                                        slot

  Power LED & keylock         J27       32-bit VESA Local bus      S3
                                        slot

  Reset switch                J28

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     CMOS memory normal operation             J2           pins 1 & 2
                                                              closed

      CMOS memory clear                        J2           pins 2 & 3
                                                              closed

     On board battery enabled                 J3           pins 1 & 2
                                                              closed

      On board battery disabled                J3           pins 2 & 3
                                                              closed

     Western Digital HDD (WDAC2340)           J5           pins 1 & 2
      not installed                                           closed

      Western Digital HDD (WDAC2340)           J5           pins 2 & 3
      installed                                               closed

              DRAM CONFIGURATION

      Size          Bank 0          Bank 3

      1MB         (4) 256K x 9       NONE

      2MB         (4) 256K x 9   (4) 256K x 9

      4MB         (4) 1M x 9         NONE

      5MB         (4) 256K x 9    (4) 1M x 9

      8MB         (4) 1M x 9      (4) 1M x 9

      16MB        (4) 4M x 9         NONE

      20MB        (4) 1M x 9      (4) 4M x 9

      32MB        (4) 4M x 9      (4) 4M x 9

                  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

                        CACHE JUMPER CONFIGURATION

  Size     J7     J8     J9        J10      J11       J12     J15    J16

  64KB     Open    2    Open      Open      Open     Open     1 &     1 &
                   &                                           2      2
                  3

  128KB    2 &     1    Closed    Open     Closed    Open     1 &     2 &
            3      &                                           2      3
                  2

  256KB    1 &     2    Closed    Closed   Closed    Closed   2 &     2 &
            2      &                                           3      3
                  3

  Note:Pins designated should be in the closed position.

                          CPU SPEED CONFIGURATION

  Speed     J20      SW1/switch   SW1/switch    SW1/switch     SW1/switch
                         1            2             3              4

  20MHz   Closed        Off          Off            On            Off

  25MHz    Open         On            On           Off            On

  33MHz    Open         On           Off            On            On

  40MHz    Open         Off          Off            On            Off

   50i     Open         On            On           Off            On
   MHz

  50MHz    Open         Off          Off           Off            Off

   66i     Open         On           Off            On            On
   MHz

                            CPU TYPE CONFIGURATION

   Type      J13   J14     J17     J18      J19     J20     J21     J24   J30

  80486SX    1 &   Open    Open    Open     Open    N/A    Closed   1 &   2 &
             2                                                      2     3

  CX486SX    2 &  Closed    1 &    Open     Open    Open   Closed   1 &   2 &
             3              2                                       2     3

  80486DX    1 &   Open     1 &   Closed   Closed   N/A    Open     1 &   2 &
             2              2                                       2     3

  CX486SX    2 &  Closed    1 &   Closed   Closed   Open   Open     1 &   2 &
             3              2                                       2     3

  ODP486SX   1 &   Open     1 &   Closed   Closed   N/A    Open     1 &   2 &
             2              2                                       2     3

  80486DX2   1 &   Open     1 &   Closed   Closed   N/A    Open     1 &   2 &
             2              2                                       2     3

  Note: Pins designated should be in the closed position.

                  VESA WAIT STATE/BUS SPEED CONFIGURATION

  CPU speed     Wait states        J6             J22            J23

     33MHz        0 wait       pins 1 & 2     pins 1 & 2     pins 1 & 2
                  states         closed         closed          closed

    > 33MHz     1 wait state    pins 2 & 3     pins 2 & 3     pins 2 & 3
                                 closed         closed          closed

