COMPAQ COMPUTER CORPORATION

PRESARIO 400 SERIES

Processor

80486SX/80487SX/80486DX/ODP486SX/80486DX2

Processor Speed

25/33/50(internal)/66(internal)MHz

Chip Set

Compaq

Max. Onboard DRAM

16MB

Cache

None

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

Riser card, floppy drive interface, game port, IDE interface, parallel port, PS/2 mouse port, serial port

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

PS/2 mouse port

CN1

Power LED & keylock

J2

Serial port

CN2

Floppy drive interface

J3

Parallel port

CN3

Speaker

J13

Game port

CN4

External battery

J16

Modem ports

CN5

Riser Card

SL1

IDE interface

J1

   

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

CPU type select PGA

P2

pins 2 & 3 closed

 

CPU type select PQFP

P2

pins 1 & 2 closed

»

CMOS memory normal operation

P6

Open

 

CMOS memory clear

P6

Closed

»

Modem ROM select internal

P7

pins 1 & 2 closed

 

Modem ROM select external

P7

pins 2 & 3 closed

DRAM CONFIGURATION

Size

Bank 0

Bank 1

1MB

(1) 256K x 36

NONE

2MB

(1) 256K x 36

(1) 256K x 36

2MB

(1) 512K x 36

NONE

3MB

(1) 256K x 36

(1) 512K x 36

4MB

(1) 512K x 36

(1) 512K x 36

4MB

(1) 1M x 36

NONE

5MB

(1) 256K x 36

(1) 1M x 36

6MB

(1) 512K x 36

(1) 1M x 36

8MB

(1) 1M x 36

(1) 1M x 36

8MB

(1) 2M x 36

NONE

9MB

(1) 256K x 36

(1) 2M x 36

10MB

(1) 512K x 36

(1) 2M x 36

12MB

(1) 1M x 36

(1) 2M x 36

16MB

(1) 2M x 36

(1) 2M x 36

CPU TYPE CONFIGURATION

Type

P3

P4

P5

80486SX (PQFP)

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

80486SX (PGA)

pins 2 & 3 closed

pins 2 & 3 closed

pins 3 & 4 closed

80487SX

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

ODP486SX

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

80486DX

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

80486DX2

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

CPU SPEED CONFIGURATION

Speed

P1

25MHz

pins 1 & 2 closed

33MHz

pins 2 & 3 closed

50iMHz

pins 1 & 2 closed

66iMHz

pins 2 & 3 closed

MISCELLANEOUS TECHNICAL NOTE

The purpose of CN6 is unknown.