Processor

80486SX/80486DX/80486DX2/Pentium Overdrive

Processor Speed

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

Chip Set

Intel

Max. Onboard DRAM

128MB

Cache

64/128/256/512KB

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

32-bit VESA local bus slots (3), PCI bus slots (4)

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

PS/2 mouse port

J1

Reset switch

J5

Power LED & keylock

J2

32-bit VESA Local bus slots

SL1, SL2, SL3

Speaker

J3

32-bit PCI slots

P1, P2, P3, P4

Turbo switch

J4

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Factory configured - do not alter

J6

Open

»

Factory configured - do not alter

JP15

Open

»

Parity check enabled

JP16

Open

Parity check disabled

JP16

Closed

»

Monitor type select color

JP21

pins 1 & 2 closed

Monitor type select monochrome

JP21

pins 2 & 3 closed

»

Factory configured - do not alter

JP41

Open

»

Factory configured - do not alter

JP43

Open

»

Factory configured - do not alter

JP44

Open

»

Factory configured - do not alter

JP81

Open

CMOS CONFIGURATION

Type

JP22

JP23

JP26

CMOS memory normal

Closed

Open

Open

CMOS memory clear

Open

Closed

Closed

DRAM CONFIGURATION

Size

Bank 0

Bank 1

2MB

(2) 256K x 36

NONE

4MB

(2) 256K x 36

(2) 256K x 36

8MB

(2) 1M x 36

NONE

10MB

(2) 1M x 36

(2) 256K x 36

16MB

(2) 1M x 36

(2) 1M x 36

32MB

(2) 4M x 36

NONE

34MB

(2) 4M x 36

(2) 256K x 36

40MB

(2) 4M x 36

(2) 1M x 36

64MB

(2) 4M x 36

(2) 4M x 36

64MB

(2) 8M x 36

NONE

66MB

(2) 8M x 36

(2) 256K x 36

72MB

(2) 8M x 36

(2) 1M x 36

96MB

(2) 8M x 36

(2) 4M x 36

128MB

(2) 8M x 36

(2) 8M x 36

CACHE CONFIGURATION

Size

Bank 0

Bank 1

TAG

64KB

(4) 8K x 8

(4) 8K x 8

(2) 16K x 4

128KB

(4) 32K x 8

NONE

(2) 16K x 4

256KB

(4) 32K x 8

(4) 32K x 8

(2) 16K x 4

512KB

(4) 128K x 8

NONE

(2) 32K x 4

CACHE JUMPER CONFIGURATION

Size

JP6

JP7

JP8

JP9

64KB

Open

Open

Open

Open

128KB

Closed

Open

Open

Closed

256KB

Closed

Closed

Open

Closed

512KB

Closed

Closed

Closed

Closed

CACHE JUMPER CONFIGURATION (CON'T)

Size

JP10

JP11

JP17

JP18

64KB

Open

Open

pins 2 & 3 closed

pins 2 & 3 closed

128KB

Open

Open

pins 2 & 3 closed

pins 1 & 2 closed

256KB

Closed

Open

pins 1 & 2 closed

pins 2 & 3 closed

512KB

Closed

Closed

pins 1 & 2 closed

pins 1 & 2 closed

L2 CACHE CONFIGURATION

Size

JI1

JI2

JI3

Standard

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

Interleaved

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

CACHE CONTROL CONFIGURATION

Wait states

Tag bit size

JP14

JP20

O wait states

7 bit

pins 1 & 2 closed

pins 1 & 2 closed

1 wait state

8 bit

pins 2 & 3 closed

pins 2 & 3 closed

CACHE MODE CONFIGURATION (L2)

Type

JP4

JP19

L2 cache (write-through)

Open

pins 1 & 2 closed

L2 cache (write-back)

Closed

pins 1 & 2 closed

L2 cache (disabled)

N/A

pins 2 & 3 closed

CACHE MODE CONFIGURATION (PENTIUM OVERDRIVE)

Type

JP2

JP60

Overdrive (write-through)

Open

pins 1 & 2 closed

Overdrive (write-back)

Closed

pins 2 & 3 closed

CPU TYPE CONFIGURATION

Type

JP1

JP3

JP12

JP13

JP27

JP28

80486SX-20

2 & 3

1 & 2

2 & 3

2 & 3

Closed

Closed

80486SX-25

2 & 3

1 & 2

2 & 3

2 & 3

Open

Closed

80486SX-33

2 & 3

1 & 2

1 & 2

2 & 3

Closed

Open

80486DX-20

1 & 2, 3 & 4

1 & 2

2 & 3

2 & 3

Closed

Closed

80486DX-25

1 & 2, 3 & 4

1 & 2

2 & 3

2 & 3

Open

Closed

80486DX-33

1 & 2, 3 & 4

1 & 2

1 & 2

2 & 3

Closed

Open

80486DX2-50

1 & 2, 3 & 4

1 & 2

2 & 3

2 & 3

Open

Closed

80486DX2-66

1 & 2, 3 & 4

1 & 2

1 & 2

2 & 3

Closed

Open

Overdrive

1 & 2, 3 & 4

2 & 3

1 & 2

2 & 3

Closed

Open

Note: Pins designated should be in the closed position.

CPU VOLTAGE CONFIGURATION

Voltage

JP5/A

JP5/B

JP5/C

JP5/D

5.0V CPU

Open

Open

Closed

Closed

80486DX4 CPU

Open

Open

Open

Open

VESA WAIT STATE/BUS SPEED CONFIGURATION

CPU speed

Wait states

JP36

JP37

< 33MHz

0 wait states

Open

Open

> 33MHz

1 wait state

Closed

Closed

PCI ADDRESS CONFIGURATION

Address (Slot 1)

Address (Slot 2)

JP70

JP71

Address 17

Address 17

pins 1 & 2 closed

pins 1 & 2 closed

Address 28

Address 29

pins 2 & 3 closed

pins 2 & 3 closed

PCI IRQ CONFIGURATION

IRQ Type

JP33 (IRQ9)

JP34 (IRQ10)

JP35 (IRQ11)

JP38 (IRQ14)

Standard

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

Inverted

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

PCI LEVEL TRIGGER IRQ CONFIGURATION

IRQ Type

JP39

IRQ9

pins 1 & 2 closed

IRQ10

pins 3 & 4 closed

IRQ11

pins 5 & 6 closed

IRQ14

pins 7 & 8 closed

IRQ15

pins 9 & 10 closed

SYSTEM BIOS CONFIGURATION

Type

JP24

JP25

Normal

Open

pins 1 & 2 closed

Flash

Closed

pins 1 & 2 closed

Recover

Open

pins 2 & 3 closed