Processor

80486SX/80487SX/80486DX/ODP486SX/80486DX2/Pentium Overdrive

Processor Speed

20/25/33/50(internal)/66(internal)MHz

Chip Set

AMI

Max. Onboard DRAM

20MB

Cache

256KB

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2), VGA port

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

IDE interface

J2

RJ48 10BaseT connector

J35

Onboard battery

J5

SCSI LED

J37

PS/2 mouse connector

J6

Speaker

J38

External battery

J8

Reset switch

J39

Serial port 2

J11

Turbo switch

J40

Secondary cache connector

J12

BNC 10Base2 connector

J41

SCSI connector (internal)

J15

IDE interface LED

J42

Serial port 1

J16

Turbo LED

J43

SCSI 1

J17

Keyboard lock connector

J44

VGA port

J31

Parallel port

P3

AUI connector

J32

Floppy drive interface

P4

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

»

PowerGood signal from DS1231

J1

Open

PowerGood signal not from DS1231 (not installed)

J1

Closed

»

Factory configured do not alter

J3

N/A

»

Flash ROM programming disabled

J7

Open

Flash ROM programming enabled

J7

Closed

»

Factory configured do not alter

J20

Closed

»

Video memory DRAM cycle select (6 MCLK RAS)

J21

Open

Video memory DRAM cycle select (7 MCLK RAS)

J21

Closed

»

VGA controller IRQ NOT routed to IRQ9

J22

Open

VGA controller IRQ routed to IRQ9

J22

Closed

»

Enables IRQ12 for onboard PS/2 mouse

J27

pins 2 & 3 closed

Disables IRQ12 for onboard PS/2 mouse

J27

pins 1 & 2 closed

»

Enables IRQ10 for NCR SCSI I/O processor

J28

Closed

Disables IRQ10 for NCR SCSI I/O processor

J28

Open

»

Enables IRQ11 for onboard LAN controller

J29

Closed

Disables IRQ11 for onboard LAN controller

J29

Open

»

VGA onboard controller enabled

J33

Closed

VGA onboard controller disabled

J33

Open

»

CMOS memory normal operation

J34

pins 2 & 3 closed

CMOS memory clear

J34

pins 1 & 2 closed

»

Onboard SCSI termination chip enabled

J36

pins 2 & 3 closed

Onboard SCSI termination chip disabled

J36

pins 1 & 2 closed

»

Factory configured do not alter

SW1/1

Off

»

Monitor type select monochrome

SW1/2

Off

Monitor type select color

SW1/2

On

64KB Cache enabled

SW2/1, 2, 3, 4

Off

256KB Cache enabled

SW2/1, 2, 3, 4

On

SERIAL PORT IRQ CONFIGURATION

Port 1 (J16)

Port 2 (J11)

J25

J26

»

IRQ4

IRQ3

pins 1 & 2 closed

pins 1 & 2 closed

IRQ3

IRQ4

pins 2 & 3 closed

pins 2 & 3 closed

CPU FREQUENCY CONFIGURATION

Frequency

J9

J10

»

33 Mhz

Open

Open

25 MHz

Closed

Open

CPU TYPE CONFIGURATION

CPU Type

J13

J14

80486SX

pins 1 & 2 closed

pins 2 & 3 closed

80487SX

pins 2 & 3 closed

all closed

80486DX

pins 1 & 2 closed

all closed

ODP486SX

pins 2 & 3 closed

all closed

80486DX2

pins 1 & 2 closed

all closed

Pentium Overdrive

pins 2 & 3 closed

all closed

MEMORY CLOCK SPEED OF THE CLGD5426

Frequency

J23

J24

50.11 MHz

Closed

Closed

44.74 MHz

Closed

Open

41.16 MHz

Open

Closed

37.58 MHz

Open

Open

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

4MB

(1) 1M x 36

NONE

NONE

NONE

6MB

(1) 256K x 36

(1) 256K x 36

(1) 1M x 36

NONE

8MB

(1) 1M x 36

(1) 1M x 36

NONE

NONE

10MB

(1) 256K x 36

(1) 256K x 36

(1) 1M x 36

(1) 256K x 36

12MB

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

NONE

16MB

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

16MB

(1) 4M x 36

NONE

NONE

NONE

20MB

(1) 1M x 36

(1) 4M x 36

NONE

NONE

24MB

(1) 1M x 36

(1) 1M x 36

(1) 4M x 36

NONE

32MB

(1) 4M x 36

(1) 4M x 36

NONE

NONE

36MB

(1) 1M x 36

(1) 4M x 36

(1) 4M x 36

NONE

40MB

(1) 1M x 36

(1) 1M x 36

(1) 4M x 36

(1) 4M x 36

48MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

NONE

64MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36