
ATEN RESEARCH, INC.

486 LOCAL BUS MAINBOARD

Processor            80486SX/80486DX/80486DX2
Processor Speed      20/25/33/50(internal)/50/66(internal)MHz
Chip Set             OPTI
Max. Onboard DRAM    64MB
Cache                64/256KB
BIOS                 AMI
Dimensions           330mm x 218mm
I/O Options          32-bit local bus card slot
NPU Options          4167

[Image]

                                CONNECTIONS

  Purpose                 Location      Purpose                Location

  External battery      J2 pins 1 & 4   Speaker                   J6

  Turbo switch               J3         Power LED & keylock       J7

  Reset switch               J4         32-bit local bus          S1
                                        card

  Turbo LED                  J5

                        USER CONFIGURABLE SETTINGS

               Function                    Jumper           Position

     Battery type select internal           J2        pins 2 & 3 closed

      Battery type select external           J2            pins 1 & 4
                                                           connected

     Monitor type select color              JP1             closed

      Monitor type select monochrome         JP1              open

     CMOS memory normal operation           JP2       pins 1 & 2 closed

      CMOS memory clear                      JP2       pins 2 & 3 closed

     VGA card type select ISA               JP3       pins 1 & 2 closed

                                             JP4       pins 1 & 2 closed

      VGA card type select local bus         JP3       pins 2 & 3 closed
      with ET 4000 chipset
                                             JP4       pins 2 & 3 closed

      VGA card type select local bus         JP3       pins 2 & 3 closed
      with S3 chipset
                                             JP4       pins 1 & 2 closed

     I/O Bus speed select ATCLK/4           JP5              open

      I/O Bus speed select ATCLK/6           JP5             closed

     CPU speed select iOSC/2                JP9       pins 2 & 3 closed

      CPU speed select iOSC/1                JP9       pins 1 & 2 closed

                             CPU CONFIGURATION

     CPU Type              JP6               JP7                JP8

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

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

      80486SX           pins 2 & 3           open              open
                         closed

            SRAM JUMPER CONFIGURATION

   Size     JP10      JP11      JP12      JP13

   64KB     open      open      open      open

  256KB    closed    closed     open     closed

                    SRAM CONFIGURATION

     Size        Cache SRAM     TAG (U46)      TAG (U47)

     64KB        (8) 8K x 8    (1) 64K x 1    (1) 8K x 8

     256KB      (8) 32K x 8    (1) 64K x 1    (1) 32K x 8

  Note:Locations of U46 and U47 are unknown.

                            DRAM CONFIGURATION

     Size         Bank 0         Bank 1         Bank 2         Bank 3

     1MB        (4) 256K x 9      NONE           NONE           NONE

     2MB        (4) 256K x 9   (4) 256K x 9      NONE           NONE

     3MB        (4) 256K x 9   (4) 256K x 9   (4) 256K x 9      NONE

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

     5MB        (4) 1M x 9     (4) 256K x 9      NONE           NONE

     6MB        (4) 256K x 9   (4) 256K x 9   (4) 1M x 9        NONE

     7MB        (4) 256K x 9   (4) 256K x 9   (4) 256K x 9   (4) 1M x 9

     8MB        (4) 1M x 9     (4) 1M x 9        NONE           NONE

     9MB        (4) 256K x 9   (4) 1M x 9     (4) 1M x 9        NONE

     10MB       (4) 256K x 9   (4) 256K x 9   (4) 1M x 9     (4) 1M x 9

     12MB       (4) 1M x 9     (4) 1M x 9     (4) 1M x 9        NONE

     13MB       (4) 256K x 9   (4) 1M x 9     (4) 1M x 9     (4) 1M x 9

     16MB       (4) 1M x 9     (4) 1M x 9     (4) 1M x 9     (4) 1M x 9

     16MB       (4) 4M x 9        NONE           NONE           NONE

     20MB       (4) 1M x 9     (4) 4M x 9        NONE           NONE

     24MB       (4) 1M x 9     (4) 1M x 9     (4) 4M x 9        NONE

     28MB       (4) 1M x 9     (4) 1M x 9     (4) 1M x 9     (4) 4M x 9

     32MB       (4) 4M x 9     (4) 4M x 9        NONE           NONE

     36MB       (4) 1M x 9     (4) 4M x 9     (4) 4M x 9        NONE

     40MB       (4) 1M x 9     (4) 1M x 9     (4) 4M x 9     (4) 4M x 9

     48MB       (4) 4M x 9     (4) 4M x 9     (4) 4M x 9        NONE

     52MB       (4) 1M x 9     (4) 4M x 9     (4) 4M x 9     (4) 4M x 9

     64MB       (4) 4M x 9     (4) 4M x 9     (4) 4M x 9     (4) 4M x 9

