DELL COMPUTER CORPORATION

System 486D

Processor

80486SX/80487SX/80486DX

Processor Speed

16/20/25/33

Chip Set

VLSI

Max. Onboard DRAM

64MB

Cache

None

BIOS

AMI

Dimensions

329mm x 334mm

I/O Options

Bus mouse, floppy interface, IDE interface, parallel port, serial ports (2), VGA port

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

VGA port

CN1

External battery

JBAT

Parallel port

CN2

Cooling fan

JFAN

Serial port 2

CN3

VGA pass-through

JFEAT

Serial port 1

CN4

Primary floppy drive interface

JFLOP

Bus mouse port

CN5

IDE interface

JIDE

Board ground points

GND

Front panel status LCD

JVIEW

IDE interface LED

JLED

   

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Boot EEPROM select normal operation

CLRB

Open

 

Boot EEPROM clear

CLRB

Closed

»

VGA interrupt request select none

JP5 pins 1 & 2

Open

 

VGA interrupt request select IRQ9

JP5 pins 1 & 2

Closed

»

Factory configured - do not alter

JP5 pins 3 & 4

Open

»

Monitor type select color

JP5 pins 5 & 6

Closed

 

Monitor type select monochrome

JP5 pins 5 & 6

Closed

»

Factory configured - do not alter

JP5 pins 7 & 8

Open

»

Password check disabled

JP5 pins 9 & 10

Open

 

Password check enabled

JP5 pins 9 & 10

Closed

»

Monitor type select standard VGA

JP5 pins 11 & 12

Open

 

Monitor type select Multifrequency (MultiSync) VGA

JP5 pins 11 & 12

Closed

»

IOCHRDY wait state(s) disabled

JP5 pins 17 & 18

Closed

 

IOCHRDY wait state(s) enabled

JP5 pins 17 & 18

Open

»

Boot source select normal (floppy or hard drive)

JP5 pins 19 & 20

Open

 

Boot source select Boot EEPROM on AT bus

JP5 pins 19 & 20

Closed

DRAM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

Bank 3

1MB

(1) 256K x 36

NONE

NONE

NONE

2MB

(1) 256K x 36

(1) 256K x 36

NONE

NONE

3MB

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

NONE

4MB

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

4MB

(1) 1M x 36

NONE

NONE

NONE

5MB

(1) 1M x 36

(1) 256K x 36

NONE

NONE

6MB

(1) 1M x 36

(1) 256K x 36

(1) 256K x 36

NONE

7MB

(1) 1M x 36

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

8MB

(1) 1M x 36

(1) 1M x 36

NONE

NONE

9MB

(1) 1M x 36

(1) 1M x 36

(1) 256K x 36

NONE

10MB

(1) 1M x 36

(1) 1M x 36

(1) 256K x 36

(1) 256K x 36

12MB

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

NONE

13MB

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

(1) 256K x 36

16MB

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

DRAM CONFIGURATION (CON’T)

Size

Bank 0

Bank 1

Bank 2

Bank 3

16MB

(1) 4M x 36

NONE

NONE

NONE

17MB

(1) 4M x 36

(1) 256K x 36

NONE

NONE

18MB

(1) 4M x 36

(1) 256K x 36

(1) 256K x 36

NONE

19MB

(1) 4M x 36

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

20MB

(1) 4M x 36

(1) 1M x 36

NONE

NONE

21MB

(1) 4M x 36

(1) 1M x 36

(1) 256K x 36

NONE

22MB

(1) 4M x 36

(1) 1M x 36

(1) 256K x 36

(1) 256K x 36

24MB

(1) 4M x 36

(1) 1M x 36

(1) 1M x 36

NONE

25MB

(1) 4M x 36

(1) 1M x 36

(1) 1M x 36

(1) 256K x 36

28MB

(1) 4M x 36

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

32MB

(1) 4M x 36

(1) 4M x 36

NONE

NONE

33MB

(1) 4M x 36

(1) 4M x 36

(1) 256K x 36

NONE

34MB

(1) 4M x 36

(1) 4M x 36

(1) 256K x 36

(1) 256K x 36

36MB

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

NONE

37MB

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

(1) 256K x 36

40MB

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

(1) 1M x 36

48MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

NONE

49MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 256K x 36

52MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

64MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

CPU SPEED CONFIGURATION

Speed

JP1

JP2

JP3

JP4

16MHz

Open

Open

Open

Closed

20MHz

Open

Open

Closed

Open

25MHz

Open

Closed

Open

Open

33MHz

Closed

Open

Open

Open

IOCHRDY CONFIGURATION

Setting

JP5 pins 13 & 14

Signal disabled to IDE drive(s)

Closed

Signal enabled to IDE drive(s)

Open