HwMuseum | Index

DIGITAL EQUIPMENT CORPORATION

VENTURIS 486 (VER. 2.0)

Device Type

Mainboard

Processor

AM486DX2/P24D/P24T

Processor Speed

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

Chip Set

Unidentified

Video Chip Set

S3

Maximum Onboard Memory

68MB

Maximum Video Memory

1MB

Cache

128/256KB

BIOS

Phoenix

Dimensions

254mm x 218mm

I/O Options

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

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

VGA port

CN1

Floppy drive interface

CN6

Serial port

CN2

IDE interface

CN7

Serial port

CN3

IDE interface

CN8

Parallel port

CN4

Riser slot

SL1

PS/2 mouse port

CN5

   

USER CONFIGURABLE SETTINGS

Function

Label

Position

»

Write through enabled

J1

Closed

 

Write back enabled

J1

Open

»

Snoop select enabled

J18

Pins 1 & 2 closed

 

Snoop select disabled

J18

Pins 2 & 3 closed

»

On board video enabled

J19

Pins 2 & 3 closed

 

On board video disabled

J19

Pins 1 & 2 closed

»

Recovery mode normal operation

J21

Open

 

Recovery mode enabled

J21

Closed

»

Password normal operation

J23

Open

 

Password clear

J23

Closed

»

Factory configured - do not alter

SL2

Unidentified

SIMM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

4MB

4MB

None

None

8MB

4MB

(1) 1M x 36

None

12MB

4MB

(1) 1M x 36

(1) 1M x 36

12MB

4MB

(1) 2M x 36

None

16MB

4MB

(1) 1M x 36

(1) 2M x 36

20MB

4MB

(1) 2M x 36

(1) 2M x 36

20MB

4MB

(1) 4M x 36

None

24MB

4MB

(1) 1M x 36

(1) 4M x 36

28MB

4MB

(1) 2M x 36

(1) 4M x 36

36MB

4MB

(1) 4M x 36

(1) 4M x 36

36MB

4MB

(1) 8M x 36

None

SIMM CONFIGURATION (CON’T)

Size

Bank 0

Bank 1

Bank 2

40MB

4MB

(1) 1M x 36

(1) 8M x 36

44MB

4MB

(1) 2M x 36

(1) 8M x 36

52MB

4MB

(1) 4M x 36

(1) 8M x 36

68MB

4MB

(1) 8M x 36

(1) 8M x 36

Note: Bank 0 is factory installed and is not configurable. The location is unidentified.

CACHE CONFIGURATION

Size

Bank 0

Bank 1

128KB

(4) 32K x 8

None

256KB

(4) 32K x 8

(4) 32K x 8

Note: The location of the cache is unidentified.

CACHE JUMPER CONFIGURATION

Size

J2

J4

128KB

Pins 1 & 2 closed

Pins 1 & 2 closed

256KB

Pins 2 & 3 closed

Pins 2 & 3 closed

VIDEO MEMORY CONFIGURATION

Note: Board is factory installed with 1MB cache. The location is unidentified.

CPU SPEED SELECTION

Speed

J14

J15

25MHz

Open

Open

33MHz

Open

Closed

40MHz

Closed

Open

50iMHz

Open

Open

66iMHz

Open

Closed

CPU TYPE SELECTION

Type

J9

J35

AM486DX2

Pins 2 & 3 closed

Closed

P24D

Pins 1 & 2 closed

Open

P24T

Pins 1 & 2 closed

Open