SOYO COMPUTER CO., LTD.

486 VESA

Processor

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

Processor Speed

25/33/40/50(internal)/50/66(internal)MHz

Chip Set

SIS

Max. Onboard DRAM

32MB

Cache

64/128/256KB

BIOS

AMI

Dimensions

230mm x 218mm

I/O Options

32-bit VESA local bus slots (2)

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

Power LED & keylock

J17

Turbo switch

J21

Speaker

J18

Turbo LED

J22

Reset switch

J19

32-bit VESA Local bus slots

SL1 & SL2

External battery

J20

 

 

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Monitor type select monochrome

JP3

Open

 

Monitor type select color/EGA/VGA

JP3

Closed

»

CMOS memory normal operation

JP5

pins 1 & 2 closed

 

CMOS memory clear

JP5

pins 2 & 3 closed

»

Factory configured - do not alter

JP6

pins 2 & 3 closed

DRAM CONFIGURATION

Size

Bank 0

Bank 1

1MB

(4) 256K x 9

NONE

2MB

(4) 256K x 9

(4) 256K x 9

4MB

(4) 1M x 9

NONE

8MB

(4) 1M x 9

(4) 1M x 9

16MB

(4) 4M x 9

NONE

20MB

(4) 1M x 9

(4) 4M x 9

32MB

(4) 4M x 9

(4) 4M x 9

CACHE CONFIGURATION

Size

Bank 0

Bank 1

TAG

64KB

(4) 8K x 8

(4) 8K x 8

(1) 8K x 8

128KB

(4) 32K x 8

NONE

(1) 8K x 8

256KB

(4) 32K x 8

(4) 32K x 8

(1) 32K x 8

CACHE JUMPER CONFIGURATION

Size

JP14

JP15

JP21

64KB

pins 1 & 2 closed

Open

pins 2 & 3 closed

128KB

pins 2 & 3 closed

pins 1 & 2 closed

pins 2 & 3 closed

256KB

pins 2 & 3 closed

pins 2 & 3 closed

pins 1 & 2 closed

CPU TYPE CONFIGURATION

Type

JP8

JP9

JP12

JP13

80486SX (PQFP)

Open

Open

Open

pins 2 & 3 closed

80486SX (PGA)

Open

Closed

Open

pins 2 & 3 closed

80487SX

Closed

Closed

pins 2 & 3 closed

pins 1 & 2 closed

80846DX/DX2

Closed

Closed

pins 1 & 2 closed

pins 1 & 2 closed

Overdrive

Closed

Closed

pins 2 & 3 closed

pins 1 & 2 closed

CPU SPEED CONFIGURATION

Speed

JP16

JP17

JP18

25MHz

Closed

Open

Closed

33MHz

Open

Closed

Closed

40MHz

Closed

Open

Open

50iMHz

Closed

Open

Closed

50MHz

Open

Closed

Open

66iMHz

Open

Closed

Closed

VESA WAIT STATE/BUS SPEED CONFIGURATION

CPU speed

Wait states

JP19

JP20

£ 33MHz

0 wait states

pins 1 & 2 closed

pins 1 & 2 closed

> 33MHz

1 wait state

pins 2 & 3 closed

pins 2 & 3 closed