UNIDENTIFIED

A351 386SX

Processor

80386SX

Processor Speed

16/20MHz

Chip Set

UMC

Max. onboard DRAM

4MB

Cache

None

BIOS

AMI

Dimensions

330mm x 220mm

I/O Options

Floppy drive interface, game port, IDE interface, parallel port, serial ports (2), VGA feature connector

NPU Options

80387SX

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

J1

Floppy drive interface

P2

Speaker

J2

IDE interface

P3

Power LED & keylock

J3

VGA feature connector

P4

Turbo switch

J4

Serial port 2

Unknown

Reset switch

J5

Serial port 1

Unknown

IDE interface LED

J6

Parallel port

Unknown

Turbo LED

J7

Game port

Unknown

Note:J4 might not be available on future boards.

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

»

Onboard VGA enabled

JP2

pins 1 & 2 closed

 

Onboard VGA disabled

JP2

pins 2 & 3 closed

»

Monitor type select CGA

JP3

Closed

 

Monitor type select monochrome

JP3

Open

»

Factory configured - do not alter

JP4

Open

»

Battery select internal

JP5

Closed

 

Battery select 6V external

JP5

Open

»

Monitor type select color

SW1/3

Off

 

Monitor type select monochrome

SW1/3

On

»

Floppy drive interface (P2) enabled

SW1/4

Off

 

Floppy drive interface (P2) disabled

SW1/4

On

»

Parallel port select LPT1 (378-37Fh)

SW1/5

Off

 

Parallel port select LPT2 (278-27Fh)

SW1/5

On

»

IDE interface (P3) enabled

SW1/6

Off

 

IDE interface (P3) disabled

SW1/6

On

»

Game port enabled

SW1/7

Off

 

Game port disabled

SW1/7

On

»

NPU synchronous with CPU

SW1/8

Off

 

NPU asynchronous with CPU

SW1/8

On

»

CMOS memory normal operation

P1

Open

 

CMOS memory clear

P1

Closed

Note: If an EGA or VGA monitor is installed, JP3 can be on either setting.

DRAM CONFIGURATION

Size

Bank 0

Bank 1

512KB

(2) 256K x 9

None

1MB

(2) 256K x 9

(2) 256K x 9

2MB

(2) 1M x 9

None

4MB

(2) 1M x 9

(2) 1M x 9

MONITOR TYPE CONFIGURATION

MonitorType

SW2/1

SW2/2

SW2/3

SW2/4

SW2/5

CGA

On

On

On

On

On

MDA

Off

On

On

On

On

Pure MDA (no emulation)

On

Off

On

On

On

EGA

Off

Off

On

On

On

Pure EGA (no emulation)

On

On

Off

On

On

VGA Color

Off

On

Off

On

On

VGA Mono

On

Off

Off

On

On

8514

Off

Off

Off

On

On

NEC 2A (640 x 480)

On

On

On

Off

On

NEC/NEC+ (multifrequency)

Off

On

On

Off

On

NEC XL (1024 x 768)

On

Off

On

Off

On

NEC 3D (1024 x 768)

Off

Off

On

Off

On

NEC4D/NEC5D (1024 x 768)

On

On

Off

Off

On

Portrait

Off

On

Off

Off

On

Note:SW2/5 on = interlaced display. For non-interlaced display this setting should be in the Off position.

SERIAL PORT CONFIGURATION

Serial port 1

Serial port 2

SW1/switch 2

SW1/switch 2

COM1

COM2

Off

Off

COM1

Disabled

Off

Off

Disabled

COM2

On

On

Disabled

Disabled

On

On