
ASUS COMPUTER INTERNATIONAL

ISA 486S

Processor         80486SX/80487SX/80486DX
Processor Speed   20/25/33MHz
Chip Set          Symphony Haydn
Max. Onboard DRAM 32MB
Cache             64/128/256KB
BIOS              AMI
Dimensions        330mm x 218mm
I/O Options       32-bit external memory card
NPU Options       4167

[Image]

                                CONNECTIONS

  Purpose                 Location     Purpose                  Location

  Power LED & keylock       CON1       Turbo switch               CON4

  Speaker                   CON2       Reset switch               CON5

  Turbo LED                 CON3       32-bit external             S1
                                       memory card

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Power good signal detect from            JP1           pins 2 & 3
      power supply                                            closed

      Power good signal detect from            JP1           pins 1 & 2
      board                                                   closed

     Monitor type select monochrome or        JP5           pins 2 & 3
      other than CGA                                          closed

      Monitor type select CGA                  JP5           pins 1 & 2
                                                              closed

                            DRAM CONFIGURATION

          Size                   Bank 0                   Bank 1

          1MB                 (4) 256K x 9                 NONE

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

          4MB                  (4) 1M x 9                  NONE

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

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

          16MB                 (4) 4M x 9                  NONE

          17MB                 (4) 4M x 9              (4) 256K x 9

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

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

  Note:Onboard memory and external memory are independent and may be used
  in any combination.

      EXTERNAL MEMORY CARD CONFIGURATION

      Size          Bank 0          Bank 1

      1MB         (4) 256K x 9       NONE

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

      4MB         (4) 1M x 9         NONE

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

      16MB        (4) 4M x 9         NONE

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

                           CACHE CONFIGURATION

     Size          Bank 0         Bank 1       TAG (U27)      TAG (U28)

     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 8    (1) 8K x 8     (1) 8K x 8

     256KB      (4) 32K x 8    (4) 32K x 8    (1) 32K x 8       NONE

                  CACHE JUMPER CONFIGURATION

        Size                 TP7               RB1 & RB2

        64KB           pins 2 & 3 closed       Position 1

        128KB          pins 1 & 2 closed       Position 2

        256KB          pins 2 & 3 closed       Position 3

  Note:Location of TP7 is unverified.

                         CPU SWITCH CONFIGURATION

   Type      SW1/1      SW1/2      SW1/3     SW1/4      SW1/5     SW1/6

  80486SX     Off        Off        Off       Off        On         On

  80487SX      On         On        On        Off        Off       Off

  80486DX      On         On        On        Off        Off       Off

