DATAEXPERT CORPORATION

OPTI-495SX

Device Type

Mainboard

Processor

80386DX/80486SX/80487SX/80486DX/80486DX2/ODP486

Processor Speed

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

Chip Set

OPTI495SX

Maximum Onboard Memory

32MB

Cache

64/128/256KB

BIOS

AMI

Dimensions

254mm x 218mm

I/O Options

32-bit VESA local bus slot

NPU Options

80387DX

CONNECTIONS

Purpose

Location

Purpose

Location

Power LED & keylock

J1

Reset switch

J5

Speaker

J2

External battery

JP18

Turbo switch

J3

32-bit VESA local bus slot

SL1

Turbo LED

J4

   

USER CONFIGURABLE SETTINGS

Function

Label

Position

»

Factory configured - do not alter

JP8

Unidentified

»

Factory configured - do not alter

JP9

Unidentified

»

Factory configured - do not alter

JP10

Unidentified

»

Factory configured - do not alter

JP11

Unidentified

 

Monitor type select color

JP17

Closed

 

Monitor type select monochrome

JP17

Open

»

CMOS memory normal operation

JP18

Pins 2 & 3 closed

 

CMOS memory clear

JP18

Pins 3 & 4 closed

 

Battery type select external

JP18

Closed

»

Factory configured - do not alter

JP23

Unidentified

»

Factory configured - do not alter

JP29

Unidentified

SIMM 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

5MB

(4) 256K x 9

(4) 1M x 9

5MB

(4) 1M x 9

(4) 256K x 9

8MB

(4) 1M x 9

(4) 1M x 9

16MB

(4) 4M x 9

None

17MB

(4) 256K x 9

(4) 4M x 9

17MB

(4) 4M x 9

(4) 256K x 9

20MB

(4) 1M x 9

(4) 4M x 9

20MB

(4) 4M x 9

(4) 1M 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

JP6

JP7

JP12

JP13

64KB

Open

Open

Open

Pins 2 & 3 closed

128KB

Open

Closed

Closed

Pins 1 & 2 closed

256KB

Closed

Closed

Closed

Pins 2 & 3 closed

CPU SPEED SELECTION

Speed

JP14

JP15

JP16

JP22

25MHz

Pins 1 & 2 closed

Open

Closed

N/A

33MHz (386)

Pins 2 & 3 closed

Closed

Open

Closed

33MHz

Pins 1 & 2 closed

Closed

Open

N/A

40MHz (386)

Pins 2 & 3 closed

Open

Open

Open

50iMHz

Pins 1 & 2 closed

Open

Closed

N/A

50MHz

Pins 2 & 3 closed

Open

Closed

N/A

66iMHz

Pins 1 & 2 closed

Closed

Open

N/A

CPU TYPE SELECTION

Type

JP1

JP2

JP4

80486SX

Open

Pins 2 & 3 closed

Open

80487SX

Closed

Pins 1 & 2 closed

Pins 2 & 3 closed

80486DX

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed

80486DX2

Closed

Pins 1 & 2 closed

Pins 1 & 2 closed

ODP486

Closed

Pins 1 & 2 closed

Pins 2 & 3 closed

CPU TYPE SELECTION

Type

JP3

JP5

JP21

JP24

80386 (PQFP)

Pins 2 & 3 closed

Pins 1 & 2 closed

Open

Pins 1 & 2 closed

80486 (PGA)

Pins 1 & 2 closed

Pins 2 & 3 closed

Closed

Pins 2 & 3 closed

80486 (PQFPGA)

Pins 1 & 2 closed

Pins 2 & 3 closed

Open

Pins 2 & 3 closed