ACER, INC.

486 SYSTEM

Processor         80486SX/80486DX/80486DX2
Processor Speed   25/33/50(internal)/66(internal)MHz
Chip Set          Intel
Max. Onboard DRAM 36MB
Cache             64/128/256KB
BIOS              Phoenix
Dimensions        330mm x 218mm
I/O Options       32-bit riser card, floppy drive interface, IDE interface,
                  parallel port, PS/2 mouse port, serial ports (2), VGA
                  feature connector, VGA port
NPU Options       None

[Image]

                                CONNECTIONS

  Purpose                Location     Purpose                  Location

  VESA control PAL          C1        Floppy drive               CN8
  chips                               interface

  VGA port                 CN1        IDE interface              CN9

  Parallel port            CN2        VGA feature connector      CN10

  Serial port 1            CN3        Multifunction              CN11
                                      connector

  Serial port 2            CN4        Reset switch               CN12

  PS/2 mouse port          CN5        IDE interface LED          CN13

  Power controller         CN6        EPA power saving           CN14
  box connector                       relay

  Power saving             CN7        Riser Card                 SL1
  controller
  connector

                        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                J13             Closed

      On board battery disabled               J13              Open

  »   DRAM parity disabled                    J14             Closed

      DRAM parity enabled                     J14              Open

  »   On board VGA enabled                    J20           pins 1 & 2
                                                              closed

      On board VGA disabled                   J20           pins 2 & 3
                                                              closed

  »   Keylock disabled                        J27           pins 1 & 2
                                                              closed

      Keylock enabled                         J27           pins 2 & 3
                                                              closed

  »   On board memory enabled                 J28           pins 1 & 2
                                                              closed

      On board memory disabled                J28           pins 2 & 3
                                                              closed

  »   Floppy/hard drive controller            J29             Closed
      enabled

      Floppy/hard drive controller            J29              Open
      disabled

                            DRAM CONFIGURATION

       Size              Bank 0            Bank 1             Bank 2

       4MB             (4) 44256            NONE               NONE

       8MB             (4) 44256         (1) 1M x 36           NONE

       12MB            (4) 44256         (1) 1M x 36       (1) 1M x 36

       12MB            (4) 44256         (1) 2M x 36           NONE

       16MB            (4) 44256         (1) 1M x 36       (1) 2M x 36

       20MB            (4) 44256         (1) 4M x 36           NONE

       20MB            (4) 44256         (1) 2M x 36       (1) 2M x 36

       24MB            (4) 44256         (1) 1M x 36       (1) 4M x 36

       36MB            (4) 44256         (1) 4M x 36       (1) 4M x 36

  Note: Bank 0 and parity chips are factory installed and are non
  configurable.

                           CACHE CONFIGURATION

     Size          Bank 0         Bank 1      TAG (7 bit)    TAG (8 bit)

     64KB        (4) 8K x 8     (4) 8K x 8    (1) 8K x 8     (1) 16K x 4

     128KB      (4) 32K x 8        NONE       (1) 8K x 8     (1) 16K x 4

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

                        CACHE JUMPER CONFIGURATION

    Size          J5              J6             J23             J24

    64KB       pins 2 & 3     pins 2 & 3         N/A          pins 1 & 2
                closed          closed                         closed

   128KB       pins 1 & 2     pins 2 & 3      pins 2 & 3      pins 2 & 3
                closed          closed         closed          closed

   256KB       pins 1 & 2     pins 1 & 2      pins 1 & 2      pins 2 & 3
                closed          closed         closed          closed

                     CACHE JUMPER CONFIGURATION (TAG)

       Type                J5                 J6                J24

   Write through           N/A            pins 2 & 3            N/A
                                            closed

  Write back/7 bit      pins 2 & 3        pins 1 & 2           Open
                         closed             closed

  Write back/8 bit      pins 1 & 2        pins 2 & 3          Closed
                         closed             closed

                        CPU TYPE CONFIGURATION

       Type              J9                J10              J11

  80486SX (PQFP)        Open             Closed             Open

  80486SX (PGA)         Open              Open              Open

     80487SX            Open             Closed            Closed

   80486DX/DX2         Closed            Closed             Open

         CPU SPEED CONFIGURATION

        Speed                J17

        25MHz         pins 3 - 7 closed

        33MHz         pins 4 - 8 closed

       50iMHz         pins 2 - 5 closed

       66iMHz         pins 3 - 6 closed

                  VIDEO MEMORY CONFIGURATION

        Size                Bank 0               Bank 1

        512KB            (4) 256K x 4             NONE

         1MB             (4) 256K x 4         (4) 256K x 4

  Note: Bank 0 is factory installed and is non configurable.