
ANTEC, INC.

MB557

Processor           CX M1/IBM/AM K5/AM K6/Pentium
Processor Speed     75/90/100/120/125/133/150/166/200MHz
Chip Set            Intel
Video Chip Set      None
Maximum Onboard     128MB (EDO supported)
Memory
Maximum Video       1MB
Memory
Cache               256/512KB
BIOS                Award
Dimensions          280mm x 220mm
I/O Options         32-bit PCI slots (4), floppy drive interface, green PC
                    connector, IDE interfaces (2), parallel port, PS/2
                    mouse interface, serial ports (2), cache slot, IR
                    connector, USB connectors (2)
NPU Options         None

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  Floppy drive interface     CN1       PS/2 mouse interface       J99

  Serial port 1              CN2       Chassis fan power          JP1

  Serial port 2              CN3       IR connector               JP3

  Parallel port              CN4       Reset switch               JP12

  IDE interface 1             J6       Green PC connector         JP15

  IDE interface 2             J7       IDE interface LED          JP22

  USB connector              J10       Green PC LED               JP33

  USB connector              J11       32-bit PCI slots         PC1  PC4

  Speaker                    J12       Cache slot                 SL1

  Power LED & keylock        J14

                        USER CONFIGURABLE SETTINGS

                Function                      Label          Position

      Monitor type select CGA40/CGA80          JP7            Closed

      Monitor type select monochrome           JP7             Open

      Monitor type select color                JP7         Any setting

     Password normal operation                JP9             Open

      Password clear                           JP9            Closed

      Flash BIOS voltage select 12v           JP19          Pins 1 & 2
                                                              closed

      Flash BIOS voltage select 5v            JP19          Pins 2 & 3
                                                              closed

     CMOS memory normal operation            JP21             Open

      CMOS memory clear                       JP21            Closed

     Factory configured - do not alter       JP39          Pins 2 & 3
                                                              closed

     Factory configured - do not alter       JP43            Closed

     Factory configured - do not alter       JP44             Open

  Note: If Cyrix 6x86 or AMD K5 processor is installed, JP9 is not
  available.

             DRAM CONFIGURATION

     Size          Bank 0        Bank 1

      8MB        (2) 1M x 36      None

     16MB        (2) 2M x 36      None

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

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

     32MB        (2) 4M x 36      None

     32MB        (2) 2M x 36   (2) 2M x 36

     40MB        (2) 4M x 36   (2) 1M x 36

     48MB        (2) 4M x 36   (2) 2M x 36

     64MB        (2) 8M x 36      None

     64MB        (2) 4M x 36   (2) 4M x 36

                        DRAM CONFIGURATION (CONT)

          Size                    Bank 0                   Bank 1

          72MB                 (2) 8M x 36              (2) 1M x 36

          80MB                 (2) 8M x 36              (2) 2M x 36

          96MB                 (2) 8M x 36              (2) 4M x 36

          128MB                (2) 8M x 36              (2) 8M x 36

  Note: Board accepts EDO memory. Banks are interchangeable. Do not
  install SIMMs & DIMMs at the same time.

             DIMM CONFIGURATION

     Size          Bank 0        Bank 1

      8MB        (1) 1M x 64      None

     16MB        (1) 2M x 64      None

     16MB        (1) 1M x 64   (1) 1M x 64

     24MB        (1) 2M x 64   (1) 1M x 64

     32MB        (1) 4M x 64      None

     32MB        (1) 2M x 64   (1) 2M x 64

     40MB        (1) 4M x 64   (1) 1M x 64

     48MB        (1) 4M x 64   (1) 2M x 64

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

                            CACHE CONFIGURATION

          Size                   Bank 0                     SL1

          256KB               (2) 32K x 32             Not installed

          512KB               (2) 32K x 32        256KB module installed

                  CACHE JUMPER CONFIGURATION

        Size                 JP29                 JP30

        256KB          Pins 2 & 3 closed   Pins 2 & 3 closed

        512KB          Pins 1 & 2 closed   Pins 1 & 2 closed

                        CPU SPEED SELECTION (CYRIX)

  CPU speed      Clock      Multiplier       JP23      JP24       JP36
                speed

   120MHz       50MHz           2x          1 & 2      2 & 3     1 & 2, 3
                                                                 & 4, 5 &
                                                                    6

   133MHz       55MHz           2x          1 & 2      2 & 3     1 & 2, 5
                                                                   & 6

   150MHz       60MHz           2x          1 & 2      2 & 3     1 & 2, 3
                                                                   & 4

   166MHz       66MHz           2x          1 & 2      2 & 3     3 & 4, 5
                                                                   & 6

  Note: Pins designated should be in the closed position.

                         CPU SPEED SELECTION (IBM)

  CPU speed      Clock      Multiplier       JP23      JP24       JP36
                speed

   120MHz       50MHz           2x          1 & 2      2 & 3     1 & 2, 3
                                                                 & 4, 5 &
                                                                    6

   133MHz       55MHz           2x          1 & 2      2 & 3     1 & 2, 5
                                                                   & 6

   150MHz       60MHz           2x          1 & 2      2 & 3     1 & 2, 3
                                                                   & 4

   166MHz       66MHz           2x          1 & 2      2 & 3     3 & 4, 5
                                                                   & 6

  Note: Pins designated should be in the closed position.

                         CPU SPEED SELECTION (AMD)

  CPU speed      Clock      Multiplier       JP23      JP24       JP36
                speed

    75MHz       50MHz          1.5x         2 & 3      2 & 3     1 & 2, 3
                                                                 & 4, 5 &
                                                                    6

    90MHz       60MHz          1.5x         2 & 3      2 & 3     1 & 2, 3
                                                                   & 4

   100MHz       66MHz          1.5x         2 & 3      2 & 3     3 & 4, 5
                                                                   & 6

   120MHz       60MHz          1.5x         2 & 3      2 & 3     1 & 2, 3
                                                                   & 4

   133MHz       66MHz          1.5x         2 & 3      2 & 3     3 & 4, 5
                                                                   & 6

   150MHz       60MHz          1.75x        1 & 2      1 & 2     1 & 2, 3
                                                                   & 4

   166MHz       66MHz          1.75x        1 & 2      1 & 2     3 & 4, 5
                                                                   & 6

   166MHz       66MHz          2.5x         1 & 2      1 & 2     3 & 4, 5
                                                                   & 6

   200MHz       66MHz           3x          2 & 3      1 & 2     3 & 4, 5
                                                                   & 6

  Note: Pins designated should be in the closed position.

                        CPU SPEED SELECTION (INTEL)

  CPU speed      Clock      Multiplier       JP23      JP24       JP36
                speed

    75MHz       50MHz          1.5x         2 & 3      2 & 3     1 & 2, 3
                                                                 & 4, 5 &
                                                                    6

    90MHz       60MHz          1.5x         2 & 3      2 & 3     1 & 2, 3
                                                                   & 4

   100MHz       66MHz          1.5x         2 & 3      2 & 3     3 & 4, 5
                                                                   & 6

   120MHz       60MHz           2x          1 & 2      2 & 3     1 & 2, 3
                                                                   & 4

   125MHz       50MHz          2.5x         1 & 2      1 & 2     1 & 2, 3
                                                                 & 4, 5 &
                                                                    6

   133MHz       66MHz           2x          1 & 2      2 & 3     3 & 4, 5
                                                                   & 6

   150MHz       60MHz          2.5x         1 & 2      1 & 2     1 & 2, 3
                                                                   & 4

   166MHz       66MHz          2.5x         1 & 2      1 & 2     3 & 4, 5
                                                                   & 6

   200MHz       66MHz           3x          2 & 3      1 & 2     3 & 4, 5
                                                                   & 6

  Note: Pins designated should be in the closed position.

                      CPU VOLTAGE SELECTION (SINGLE)

    Voltage          J100          J105           J107           J108

     2.82v           Open          3 & 4          Open       1 & 3, 2 & 4

     2.94v          2 & 4          3 & 4          Open       1 & 3, 2 & 4

     3.10v          3 & 4          3 & 4          Open       1 & 3, 2 & 4

     3.33v          1 & 3          3 & 4          Open       1 & 3, 2 & 4

     3.53v        1 & 3, 2 &       3 & 4          Open       1 & 3, 2 & 4
                      4

  Note: Pins designated should be in the closed position.

                       CPU VOLTAGE SELECTION (DUAL)

    Voltage       V core       J100       J105        J107        J108

     3.33v        2.82v        Open       3 & 4      1 & 3, 2     Open
                                                       & 4

     3.33v        2.94v       2 & 4       3 & 4      1 & 3, 2     Open
                                                       & 4

     3.33v        3.10v       3 & 4       3 & 4      1 & 3, 2     Open
                                                       & 4

     3.44v        2.82v        Open       2 & 4      1 & 3, 2     Open
                                                       & 4

     3.44v        2.94v       2 & 4       2 & 4      1 & 3, 2     Open
                                                       & 4

     3.44v        3.10v       3 & 4       2 & 4      1 & 3, 2     Open
                                                       & 4

  Note: Pins designated should be in the closed position.

