
SOYO COMPUTER CO., LTD.

SY-25 Q/R

Processor   UMCU5S/AM486SX/80486SX/CX486DX/AM486DX/AM486DXL/
            80486DX/SL80486DX/CX486DX2/AM486DX2/80486DX2/
            SL80486DX2/AM486DX4/SL80486DX4/P24D/P24T
Processor   25/33/40/50(internal)/66(internal)/75(internal)/80(internal)/
Speed       100(internal)MHz
Chip Set    Unidentified
Video Chip  None
Set
Maximum     64MB
Onboard
Memory
Maximum     None
Video
Memory
Cache       256KB
BIOS        Award
Dimensions  254mm x 218mm
I/O Options 32-bit VESA local bus slots (3), green PC connector
NPU Options None

[Image]

                                CONNECTIONS

  Purpose                 Location    Purpose                   Location

  Power LED & keylock       J17       Turbo switch                J21

  Speaker                   J18       Turbo LED                   J22

  Reset switch              J19       Green PC connector          JP25

  External battery          J20       32-bit VESA local bus    SL1  SL3
                                      slots

                        USER CONFIGURABLE SETTINGS

                Function                     Label           Position

     CMOS memory normal operation            J20           Pins 2 & 3
                                                              closed

      CMOS memory clear                       J20           Pins 3 & 4
                                                              closed

      Battery type select external            J20             Closed

                        SIMM CONFIGURATION

      Size            Bank 0           Bank 1          Bank 2

       1MB         (4) 256K x 9         None            None

       2MB         (4) 256K x 9    (1) 256K x 36        None

       4MB          (4) 1M x 9          None            None

       5MB         (4) 256K x 9     (1) 1M x 36         None

       6MB         (4) 256K x 9    (1) 256K x 36     (1) 1M x 36

       8MB          (4) 1M x 9      (1) 1M x 36         None

      12MB          (4) 1M x 9      (1) 1M x 36      (1) 1M x 36

      16MB          (4) 4M x 9          None            None

      17MB         (4) 256K x 9     (1) 4M x 36         None

      18MB         (4) 256K x 9    (1) 256K x 36     (1) 4M x 36

      20MB          (4) 1M x 9      (1) 4M x 36         None

      24MB          (4) 1M x 9      (1) 1M x 36      (1) 4M x 36

      32MB          (4) 4M x 9      (1) 4M x 36         None

      36MB          (4) 1M x 9      (1) 4M x 36      (1) 4M x 36

      48MB          (4) 4M x 9      (1) 4M x 36      (1) 4M x 36

      64MB         (4) 16M x 9          None            None

       1MB             None        (1) 256K x 36        None

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

       2MB             None        (1) 512K x 36        None

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

       4MB             None         (1) 1M x 36         None

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

       6MB          (4) 1M x 9     (1) 256K x 36    (1) 256K x 36

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

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

       8MB             None         (1) 2M x 36         None

      12MB          (4) 1M x 9      (1) 1M x 36      (1) 1M x 36

      12MB             None         (1) 1M x 36      (1) 2M x 36

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

                        SIMM CONFIGURATION (CONT)

       Size             Bank 0            Bank 1             Bank 2

       16MB              None          (1) 4M x 36            None

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

       18MB           (4) 4M x 9      (1) 256K x 36       (1) 256K x 36

       18MB              None         (1) 512K x 36        (1) 4M x 36

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

       24MB           (4) 4M x 9       (1) 1M x 36         (1) 1M x 36

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

       32MB              None          (1) 8M x 36            None

       36MB           (4) 4M x 9       (1) 1M x 36         (1) 4M x 36

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

       48MB           (4) 4M x 9       (1) 4M x 36         (1) 4M x 36

       48MB              None          (1) 4M x 36         (1) 8M x 36

       64MB              None          (1) 8M x 36         (1) 8M x 36

            Note: Board also accepts x 32 SIMMs. Do not use any other
            combination of SIMM configuration.

                            CACHE CONFIGURATION

       Size              Bank 0            Bank 1              TAG

     256KB (A)        (4) 32K x 8        (4) 32K x 8     (1) 16K/32K x 8

     256KB (B)        (4) 64K x 8           None         (1) 16K/32K x 8

                        CACHE JUMPER CONFIGURATION

         Size                     JP9                      JP10

       256KB (A)           Pins 2 & 3 closed         Pins 2 & 3 closed

       256KB (B)           Pins 1 & 2, 3 & 4         Pins 1 & 2 closed
                                closed

            CPU SPEED SELECTION

   Speed      JP4        JP5        JP6

   25MHz      Open       Open     Closed

   33MHz     Closed     Closed    Closed

   40MHz      Open      Closed    Closed

  50iMHz      Open       Open     Closed

  66iMHz     Closed     Closed    Closed

  75iMHz      Open       Open     Closed

  80iMHz      Open      Closed    Closed

  100iMHz    Closed     Closed    Closed

                            CPU TYPE SELECTION

        Type           JP11        JP12       JP13      JP14       JP15

      UMC U5S          2 & 3      2 & 3       2 & 3     2 & 3     2 & 3

      AM486SX          Open       2 & 3       2 & 3     2 & 3     2 & 3

      80486SX          Open       2 & 3       2 & 3     2 & 3     2 & 3

    CX486DX (5v)       1 & 2,    1 & 2, 3     1 & 2,    2 & 3     2 & 3
                       3 & 4     & 4, 5 &     3 & 4
                                    6

      AM486DX          Open       2 & 3       1 & 2,    2 & 3     2 & 3
                                              3 & 4

   AM486DXL (5v)       2 & 3      2 & 3       1 & 2,    2 & 3     2 & 3
                                              3 & 4

      80486DX          Open       2 & 3       1 & 2,    2 & 3     2 & 3
                                              3 & 4

     SL80486DX         1 & 2      1 & 2       1 & 2,    2 & 3     2 & 3
                                              3 & 4

   CX486DX2 (5v)       1 & 2,    1 & 2, 3     1 & 2,    2 & 3     2 & 3
                       3 & 4     & 4, 5 &     3 & 4
                                    6

     CX486DX2-66       1 & 2,    1 & 2, 3     1 & 2,    1 & 2     1 & 2
       (3.6v)          3 & 4     & 4, 5 &     3 & 4
                                    6

  CX486DX2-80 (4v)     1 & 2,    1 & 2, 3     1 & 2,    1 & 2     1 & 2
                       3 & 4     & 4, 5 &     3 & 4
                                    6

      AM486DX2         Open       2 & 3       1 & 2,    2 & 3     2 & 3
                                              3 & 4

     AM486DX2-80       Open       2 & 3       1 & 2,    1 & 2     1 & 2
      (3.45v)                                 3 & 4

   AM486DXL2 (5v)      2 & 3      2 & 3       1 & 2,    2 & 3     2 & 3
                                              3 & 4

      80486DX2         Open       2 & 3       1 & 2,    2 & 3     2 & 3
                                              3 & 4

     SL80486DX2        1 & 2      1 & 2       1 & 2,    2 & 3     2 & 3
                                              3 & 4

  AM486DX4 (3.45v)     Open       2 & 3       1 & 2,    1 & 2     1 & 2
                                              3 & 4

     SL80486DX4        1 & 2      1 & 2       1 & 2,    1 & 2     1 & 2
      (3.45v)                                 3 & 4

  SL80486DX4 (5v)      1 & 2      1 & 2       1 & 2,    2 & 3     2 & 3
                                              3 & 4

        P24D           1 & 2,    1 & 2, 4     1 & 2,    2 & 3     2 & 3
                       4 & 5       & 5        3 & 4

        P24T           1 & 2      1 & 2       1 & 2,    2 & 3     2 & 3
                                              3 & 4

  Note: Pins designated should be in the closed position.

                        CPU TYPE SELECTION (CONT)

        Type              JP16         JP17         JP18         JP19

       UMC U5S           2 & 3        3 & 4        1 & 2         Open

       AM486SX           2 & 3         Open         Open         Open

       80486SX           2 & 3         Open         Open         Open

    CX486DX (5v)         2 & 3        1 & 2      2 & 3, 4 &      2 & 3
                                                     5

       AM486DX           2 & 3        1 & 2         Open         Open

    AM486DXL (5v)        2 & 3      1 & 2, 3 &     1 & 2         Open
                                        4

       80486DX           2 & 3        1 & 2         Open         Open

      SL80486DX          2 & 3        1 & 2        5 & 6       1 & 2, 3 &
                                                                   4

    CX486DX2 (5v)        2 & 3        1 & 2      2 & 3, 4 &      2 & 3
                                                     5

  CX486DX2-66 (3.6v)     1 & 2        1 & 2      2 & 3, 4 &      2 & 3
                                                     5

  CX486DX2-80 (4v)       1 & 2        1 & 2      2 & 3, 4 &      2 & 3
                                                     5

      AM486DX2           2 & 3        1 & 2         Open         Open

     AM486DX2-80         1 & 2        1 & 2         Open         Open
       (3.45v)

   AM486DXL2 (5v)        2 & 3      1 & 2, 3 &     1 & 2         Open
                                        4

      80486DX2           2 & 3        1 & 2         Open         Open

     SL80486DX2          2 & 3        1 & 2        5 & 6       1 & 2, 3 &
                                                                   4

  AM486DX4 (3.45v)       1 & 2        1 & 2         Open         Open

  SL80486DX4 (3.45v)     1 & 2        1 & 2        5 & 6       1 & 2, 3 &
                                                                   4

   SL80486DX4 (5v)       2 & 3        1 & 2        5 & 6       1 & 2, 3 &
                                                                   4

        P24D             2 & 3        1 & 2      3 & 4, 5 &    1 & 2, 3 &
                                                     6             4

        P24T             2 & 3        2 & 3        5 & 6       1 & 2, 3 &
                                                                   4

  Note: Pins designated should be in the closed position.

                            CPU TYPE SELECTION

         Type              JP20             JP26              JP27

       UMC U5S             Open             Open              Open

       AM486SX             Open             Open              Open

       80486SX             Open             Open              Open

     CX486DX (5v)          Open             Open              Open

       AM486DX             Open             Open              Open

    AM486DXL (5v)          Open             Open              Open

       80486DX             Open             Open              Open

      SL80486DX            Open             Open              Open

    CX486DX2 (5v)          Open             Open              Open

  CX486DX2-66 (3.6v)       Open             Open        Pins 3 & 4closed

   CX486DX2-80 (4v)        Open             Open        Pins 5 & 6closed

       AM486DX2            Open             Open              Open

  AM486DX2-80 (3.45v)      Open            Closed       Pins 1 & 2 closed

    AM486DXL2 (5v)         Open             Open              Open

       80486DX2            Open             Open              Open

      SL80486DX2           Open             Open              Open

   AM486DX4 (3.45v)        Open             Open        Pins 1 & 2 closed

  SL80486DX4 (3.45v)       Open             Open        Pins 1 & 2 closed

   SL80486DX4 (5v)         Open             Open              Open

         P24D              Open             Open              Open

         P24T              Open             Open              Open

  Note: Pins designated should be in the closed position.

