AST RESEARCH, INC.

PREMMIA MS 486

Processor

80486SX/80486DX/ODP486SX/80486DX2/80486DX4/Pentium Overdrive

Processor Speed

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

Chip Set

AST

Max. Onboard DRAM

128MB

Cache

64/256KB

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

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

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

VGA port

CN1

External battery

J26

Parallel port

CN2

Speaker

J27

Serial port 2

CN3

Chassis fan power

J28

Serial port 1

CN4

Front panel connector

J29

PS/2 mouse port

CN5

Chassis fan power

J32

IDE interface 2

J22

IDE interface LED

J40

IDE interface 1

J23

Riser Card

SL1

Floppy drive interface

J24

   

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

»

Cache type select write back

E1

Open

 

Cache type select write through

E1

Closed

»

Factory configured - do not alter

E6

pins 1 & 2 closed

»

CMOS memory normal

E8

Open

 

CMOS memory clear

E8

Closed

»

Flash BIOS write protect enabled

SW1/1

Off

 

Flash BIOS write protect disabled

SW1/1

On

»

Password enabled

SW1/2

On

 

Password disabled

SW1/2

Off

»

Monitor type select color

SW1/3

On

 

Monitor type select monochrome

SW1/3

Off

»

System setup enabled

SW1/4

On

 

system setup disabled

SW1/4

Off

»

Factory configured - do not alter

SW1/5

Off

»

Factory configured - do not alter

SW1/6

Off

»

Factory configured - do not alter

SW1/7

Off

»

Factory configured - do not alter

SW1/8

Off

DRAM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

Bank 3

2MB

(1) 256K x 36

(1) 256K x 36

NONE

NONE

3MB

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

NONE

4MB

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

4MB

(1) 1M x 36

NONE

NONE

NONE

8MB

(1) 1M x 36

(1) 1M x 36

NONE

NONE

9MB

(1) 1M x 36

(1) 1M x 36

(1) 256K x 36

NONE

10MB

(1) 1M x 36

(1) 1M x 36

(1) 256K 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

32MB

(1) 4M x 36

(1) 4M x 36

NONE

NONE

33MB

(1) 4M x 36

(1) 4M x 36

(1) 256K x 36

NONE

34MB

(1) 4M x 36

(1) 4M x 36

(1) 256K x 36

(1) 256K x 36

36MB

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

NONE

40MB

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

(1) 1M x 36

48MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

NONE

49MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 256K x 36

64MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

64MB

(1) 8M x 36

(1) 8M x 36

NONE

NONE

65MB

(1) 8M x 36

(1) 8M x 36

(1) 256K x 36

NONE

66MB

(1) 8M x 36

(1) 8M x 36

(1) 256K x 36

(1) 256K x 36

DRAM CONFIGURATION (CON’T)

Size

Bank 0

Bank 1

Bank 2

Bank 3

68MB

(1) 8M x 36

(1) 8M x 36

(1) 1M x 36

NONE

72MB

(1) 8M x 36

(1) 8M x 36

(1) 1M x 36

(1) 1M x 36

96MB

(1) 8M x 36

(1) 8M x 36

(1) 8M x 36

NONE

128MB

(1) 8M x 36

(1) 8M x 36

(1) 8M x 36

(1) 8M x 36

CACHE CONFIGURATION

Size

Bank 0

Bank 1

TAG

64KB

(4) 8K x 8

(4) 8K x 8

(1) 8K x 8

256KB

(4) 32K x 8

(4) 32K x 8

(1) 32K x 8

CACHE JUMPER CONFIGURATION

Size

E5

64KB

Open

256KB

Closed

CPU TYPE CONFIGURATION

Type

E1

E2

E3

E4

80486SX (PQFP)

Open

pins 2 & 3 closed

pins 1 & 2 closed

Open

ODP486SX

Open

pins 2 & 3 closed

pins 1 & 2 closed

Open

80486DX (write back)

Open

pins 1 & 2 closed

pins 2 & 3 closed

Open

80486DX/DX2

Open

pins 1 & 2 closed

pins 1 & 2 closed

Open

80486DX4

Open

pins 1 & 2 closed

pins 1 & 2 closed

Open

Pentium Overdrive

Open

pins 2 & 3 closed

pins 2 & 3 closed

Open

CPU SPEED CONFIGURATION

Speed

E7

E9

25MHz

pins 1 & 2 closed

Closed

33MHz

pins 2 & 3 closed

Open

50iMHz

pins 1 & 2 closed

Closed

66iMHz

pins 2 & 3 closed

Open