FIRST INTERNATIONAL COMPUTER, INC.

LEO 486-PSD-10

Processor

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

Processor Speed

25/33/40/50(internal)/66(internal)/100(internal)MHz

Chip Set

INTEL

Max. Onboard DRAM

128MB

Cache

64/256KB

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

Floppy drive interface, IDE interface,mouse connector, parallel port,

P/S2 mouse connector, serial ports (2), VGA connector

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

Bus mouse connector

CN1

IDE LED

J11

P/S2 mouse connector

CN4

Green power supply connector

J16

Floppy drive interface

CN6

Turbo switch

J29

IDE connector

CN7

Turbo LED

J30

Serial port 1

CN8

Reset switch

J31

Serial port 2

CN9

Speaker

J32

Parallel port

CN10

Power LED & keylock

J33

SCSI connector

CN11

PCI slots

PCI 1, 2, & 3

SCSI busy LED

J7

3.3V daughter board (80486DX4)

PS3V

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

CPU generate parity

J4

pins 1 & 2 closed

 

DPU generate parity

J4

pins 2 & 3 closed

»

Do not force parity error

J5

pins 1 & 2 closed

 

Force parity error

J5

pins 2 & 3 closed

»

SCSI enable

J6

closed

 

SCSI disable

J6

open

»

SCSI power source from peripheral device

J8

open

 

SCSI power source from system

J8

closed

 

IDE connector pin 27 linked to IOCHRDY signal

J9

closed

 

IDE connector pin 27 open

J9

open

 

IDE connector pin 28 linked to BALE signal

J10

closed

 

IDE connector pin 28 open

J10

open

»

Normal operation

J17

Open

 

Clear password

J17

closed

»

Saturn B-step chip

J23

pins 1 & 2 closed

 

Saturn II/II-50

J23

pins 2 & 3 closed

»

Cache set at 256K

J24

pins 2 & 3 closed

 

Cache set at 64K

J24

pins 1 & 2 closed

 

Level 2 write-back cache

J25

pins 1 & 2 closed

 

Level 2 write-through cache

J25

pins 2 & 3 closed

»

80486DX4 2.5X mode

J26

pins 2 & 3 closed

 

80486DX4 2X mode

J26

pins 1 & 2 closed

 

80486DX4 3X mode

J26

open

»

Pentium Overdrive internal write-back cache

J27

pins 1 & 2 closed

 

Pentium Overdrive internal write-through cache

J27

pins 2 & 3 closed

»

No cache wait state

JF3

pins 2 & 3 closed

 

One cache wait state

JF3

pins 1 & 2 closed

 

Saturn II/II-50 chipset with SL-enhan/DX4/Pentium overdrive

JF9

pins 2 & 3 closed

 

Saturn II/II-50 chipset with other CPUs

JF9

pins 1 & 2 closed

 

Saturn II/II-50 chipset for Saturn B-step chipset use

JF9

open

»

PCI SCSI IRQ at IRQ9

JN1

pins 1 & 2 closed

 

PCI SCSI IRQ at IRQ11

JN1

pins 2 & 3 closed

DRAM CONFIGURATION

Size

Bank 0

Bank 1

Bank 2

Bank 3

2MB

(1) 256K x 36

(1) 256K x 36

NONE

NONE

4MB

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

(1) 256K x 36

8MB

(1) 1M x 36

(1) 1M x 36

NONE

NONE

10MB

(1) 1M x 36

(1) 1M x 36

(1) 256K x 36

(1) 256K x 36

16MB

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

(1) 1M x 36

32MB

(1) 4M x 36

(1) 4M x 36

NONE

NONE

34MB

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

(1) 256K x 36

40MB

(1) 4M x 36

(1) 4M x 36

(1) 1M x 36

(1) 1M x 36

64MB

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

(1) 4M x 36

64MB

(1) 16M x 36

(1) 16M x 36

NONE

NONE

DRAM CONFIGURATION (CONTINUED)

Size

Bank 0

Bank 1

Bank 2

Bank 3

66MB

(1) 16M x 36

(1) 16M x 36

(1) 256K x 36

(1) 256K x 36

72MB

(1) 16M x 36

(1) 16M x 36

(1) 1M x 36

(1) 1M x 36

96MB

(1) 16M x 36

(1) 16M x 36

(1) 16M x 36

(1) 16M x 36

128MB

(1) 16M x 36

(1) 16M x 36

(1) 16M x 36

(1) 16M x 36

Note:A {(1) 32M x 36} is a double RAS SIMM.

CACHE CONFIGURATION

Size

Data RAM

TAG RAM

U32 (dirty bit)

64KB

(8) 8K x 8

(1) 1K x 8

64K x 1

256KB

(8) 32K x 8

(1) 32K x 8

64K x 1

CACHE JUMPER CONFIGURATION

Size

J14

J15

J18

J19

64KB

Open

Open

Open

Open

256KB

Closed

Closed

Closed

Closed

CACHE INTERLEAVE CONFIGURATION

Type

J20

J21

J22

Interleave

pins 2 & 3 closed

pins 1 & 2 closed

pins 1 & 2 closed

Standard

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

Note:Interleave setting is for the Saturn II-50 chipset only.

CPU TYPE CONFIGURATION

Type

JC1

JC2, JC3

80486SX

Open

pins 2 & 3

80486DX

Open

pins 1 & 2

80486DX2

Open

pins 1 & 2

80486DX4

Open

pins 1 & 2

Pentium Overdrive

Closed

pins 1 & 2

CPU TYPE CONFIGURATION (CONTINUED)

Type

JC4, J12

JC5

JC6

80486SX 1

Closed

Open

pins 1 & 2

80486SX 2

Closed

Open

pins 1 & 2

80486DX 1

Closed

Open

pins 1 & 2

80486DX 2

Closed

Open

pins 1 & 2

80486DX2 1

Closed

Open

pins 1 & 2

80486DX2 2

Closed

Open

pins 1 & 2

80486DX4 1

Closed

Open

pins 1 & 2

80486DX4 2

Closed

Closed

pins 2 & 3

CPU TYPE CONFIGURATION (CONTINUED)

Type

JC4, J12

JC5

JC6

SL enhanced 1

Closed

open

pins 1 & 2

SL enhanced 2

Closed

closed

pins 2 & 3

Pentium Overdrive 1

Open

open

pins 1 & 2

Pentium Overdrive 2

Open

closed

pins 2 & 3

Note: 1 denotes Saturn B-step chipset used with CPU.

2 denotes Saturn II/II-50 chipset used with CPU.

CPU CLOCK (VT8225N) CONFIGURATION

Speed

JK1

JK2

CLK2 50 Mhz

pins 1 & 2 closed

pins 2 & 3 closed

CLK2 66.6 Mhz

pins 2 & 3 closed

pins 1 & 2 open

CPU SPEED CONFIGURATION

Speed

JF6

JF7

Reserved

pins 2 & 3

pins 1 & 2

25MHz

pins 1 & 2

pins 1 & 2

33Mhz

pins 1 & 2

pins 2 & 3

50iMHz

pins 1 & 2

pins 1 & 2

50iMHz 1

pins 2 & 3

pins 2 & 3

66iMHz

pins 1 & 2

pins 2 & 3

Note: 1 denotes Saturn II-50 chipset only.

PCI1 IRQ SELECTION

Jumper

IRQ

Setting

JI1

IRQ5

pins 1 & 2 closed

JI2

IRQ9

pins 1 & 2 closed

JI3

IRQ10

pins 1 & 2 closed

JI4

IRQ11

pins 1 & 2 closed

JI5

IRQ12

pins 1 & 2 closed

JI6

IRQ14

pins 1 & 2 closed

JI7

IRQ15

pins 1 & 2 closed

PCI2 & PCI3 IRQ SELECTION

Jumper

IRQ

Setting

JI1

IRQ5

pins 2 & 3 closed

JI2

IRQ9

pins 2 & 3 closed

JI3

IRQ10

pins 2 & 3 closed

JI4

IRQ11

pins 2 & 3 closed

JI5

IRQ12

pins 2 & 3 closed

JI6

IRQ14

pins 2 & 3 closed

JI7

IRQ15

pins 2 & 3 closed

TAG ADDRESS CONFIGURATION

Address

JF1

JF2

8-bit

pins 1 & 2 closed

pins 1 & 2 closed

7-bit

pins 1 & 2 closed

pins 2 & 3 closed

9-bit

pins 2 & 3 closed

pins 1 & 2 closed

Reserved

pins 2 & 3 closed

pins 2 & 3 closed

MISCELLANEOUS TECHNICAL NOTE

Note:1. When using the PCI1 slot on the mainboard, jumper choice should only be limited to pins 1 & 2 of jumpers JI1 to JI7

2. When using PCI2 or PCI3 slots on the mainboard, jumper choice should only be limited to pins

2 & 3 of jumpers JI1 to JI7.

3. When using the Saturn B-step chipset, PCI1 slot serves as the master slot while PCI2 and PCI

3 slots serve as slave slots.

4. When using the Saturn II/II-50 chipset, PCI1, PCI2, PCI3 slots can serve both as master or

slave slot.