Msi MS-6785 user Manual

Getting Started

Chapter 1. Getting
Started

Getting Started

Thank you for purchasing the MS-6785 v1.X Micro ATX

mainboard. The MS-6785 is based on SiS®648FX & SiS®963
chipsets for optimal system efficiency. Designed to fit the ad­vanced Intel® Pentium® 4 processors in the 478 pin package, the
MS-6785 delivers a high performance and professional desktop
platform solution.

1-1

MS-6785 M-ATX Mainboard

Mainboard Specifications

CPU

h Socket 478 for P4 processors with 400/533/800 MHz (100/133/200MHz QDIR).
h Core frequency up to 3.2GHz.

Chipset

h SiS®648FX (839 pin BGA)

- Supports Intel® Pentium® 4 processors with data transfer rate up to 800
MHz.

- Supports 64-bit high performance DDR400/333/266 memory controller.

- Supports AGP 8X/4X interface at 0.8v or 4x at 1.5v with fast write
transaction.

- Supports bi-directional 16-bit data bus with 1GHz bandwidth MuTIOL.

h SiS®963 (371 pin BGA)

- Supports high throughput SiS MuTIOL 1GHz interconnecting to SiS®963
media I/O.

- Supports Dual-IDE A T A 66/100/133.

- Integrated Direct Sound AC97 audio.

- Low pin count interface for SIO.

- Advanced power management and PC2001 compliance.

- High speed USB 2.0 controller, 480Mb/s.

Main Memory

h Supports four memory banks using two 184-pin DDR DIMMs.
h Supports up to 2GB PC3200/2700/2100DDR SDRAMs.
h Supports 2.5v DDR SDRAM.

Slots

h One AGP (Accelerated Graphics Port) slot

- Supports AGP 3.0 4x/8x.

h Three 32-bit PCI bus slots.

- Support 3.3v/5v PCI bus interface.

- The second PCI slot in BLUE supports 2 master devices.

On-Board IDE

h Dual IDE controllers integrated in SiS 963.
h Supports P/O, Bus Master, Ultra DMA66/100/133 operation.
h Can connect up to four IDE devices.

1-2

Getting Started

On-Board Peripherals

h On-Board Peripherals include:

- One floppy port supports 2 FDDs with 360K, 720K, 1.2M, 1.44M and

2.88Mbytes

- One serial port (COM A)

- One parallel port supports SPP/EPP/ECP mode (Optional)

- One RJ-45 LAN port

- Vertical audio ports

- One RCA_SPDIF In & one RCA_SPDIF Out

- Three 1394 ports [Rear x 2 (6 / 4 pins) + Front x 1 (6 pins)]

- Six USB 2.0 ports (Rear * 2/ Front * 4)

Onboard IEEE1394

h Integrated in SiS®963.
h Agere FW803 PHY.

Audio

h S/W C-Media 9739A 5.1 channel with SPDIF in/out.

LAN

h VIA® VT6103 LAN controller.

BIOS

h The mainboard BIOS provides “Plug & Play” BIOS which detects the pe-

ripheral devices and expansion cards of the board automatically.

h The mainboard provides a Desktop Management Interface (DMI) function

which records your mainboard specifications.

Dimension

h Micro ATX Form Factor: 24.0 cm x 24.5 cm.

Mounting

h 6 mounting holes.

1-3

MS-6785 M-ATX Mainboard

Mainboard Layout

Top : mo us e
Bottom: keyboard

JLPT1

T: RJ 45 LA N j ac k
B: USB ports

1394 port

Mini1394 port

T:SPDIF in
B:SPDIF out

Line-Out

Line-Out
Line-Out

Line-Out
Line-Out

Line-Out

T:M ic
B:Line-In

VT6103

JSPDIF1

Codec

CPUFAN1

J9

AGERE
FW803

VIA

JPW1

SiS

BIOS

CN8

Winbond
83697HF

648FX

AGP Slot

PCI Slot 1

PCI Slot 2

PCI Slot 3

BATT

JVEDIO1

JAUDIO1

JBAT1

+

MS-6785v1.X Micro A TX Mainboard

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1

2

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D

D

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1

2

R

R

D

D

D

SiS

963

JUSB1

D

F_P1

1-4

Hardware Setup

Chapter 2. Hardware
Setup

Hardware Setup

This chapter provides you with the information about hard­ware setup procedures. While doing the installation, be careful
in holding the components and follow the installation procedures.
For some components, if you install in the wrong orientation,
the components will not work properly.

Use a grounded wrist strap before handling computer
components. Static electricity may damage the components.

2-1

MS-6785 M-ATX Mainboard

Quick Components Guide

Back Panel
I/O, p.2-10

J7, p.2-23

J9, p.2-20

AGP Slot, p.2-25

JSPDIF1, p.2-21

JVIDEO1, p.2-18

JPW1, p.2-9

CPU, p.2-3

CPUFAN1, p.2-17

DIMM1/2,

p.2-7

CONN1,

p.2-9

FDD1,

p.2-15

IDE2,

p.2-16

IDE1,

p.2-16

JUSB1,

p.2-19

PCI Slots,

p.2-25

2-2

JBAT1, p.2-24

F_P1, p.2-18JAUDIO1, p.2-22

Hardware Setup

Central Processing Unit: CPU

The mainboard supports Intel® Pentium® 4 processors in the 478 pin

package. The mainboard uses a CPU socket called PGA478 for easy CPU
installation. When you are installing the CPU, make sure the CPU has a heat
sink and a cooling fan attached on the top to prevent overheating. If you
do not find the heat sink and cooling fan, contact your dealer to purchase and
install them before turning on the computer.

CPU Core Speed Derivation Procedure

If CPU Clock = 100MHz

Core/Bus ratio = 14

then CPU core speed = Host Clock x Core/Bus ratio

= 100MHz x 14
= 1.4 GHz

MSI Reminds You...

Overheating

Overheating will seriously damage the CPU and system, al­ways make sure the cooling fan can work properly to protect
the CPU from overheating.

Replacing the CPU

While replacing the CPU, always turn off the ATX power sup­ply or unplug the power supply’s power cord from grounded
outlet first to ensure the safety of CPU.

Overclocking

This motherboard is designed to support over clocking. However,
please make sure your components are able to tolerate such
abnormal setting, while doing overclocking. Any attempt to
operate beyond product specifications is not r ecommended. We

do not guarantee the damages or risks caused by inadequate
operation or beyond product specifications.

2-3

MS-6785 M-ATX Mainboard

CPU Installation Procedures for Socket 478

1. Please turn off the power and
unplug the power cord before
installing the CPU.

Open Lever

2. Pull the lever sideways away
from the socket. Make sure to
raise the lever up to a 90-de­gree angle.

3. Look for the gold arrow. The
gold arrow should point to­wards the lever pivot. The
CPU can only fit in the cor­rect orientation.

4. If the CPU is correctly
installed, the pins should be
completely embedded into the
socket and can not be seen.
Please note that any violation
of the correct installation pro­cedures may cause permanent
damages to your mainboard.

5. Press the CPU down firmly
into the socket and close the
lever. As the CPU is likely to
move while the lever is being
closed, always close the lever
with your fingers pressing
tightly on top of the CPU to
make sure the CPU is prop­erly and completely embed­ded into the socket.

Sliding

Plate

Gold arrow

Gold arrow

Gold arrow

Press down

the CPU

90 degree

Correct CPU placement

Incorrect CPU placeme n t

O

X

Close
Lever

2-4

Hardware Setup

Installing the CPU Fan

As processor technology pushes to faster speeds and higher performance,
thermal management becomes increasingly important. To dissipate heat, you
need to attach the CPU cooling fan and heatsink on top of the CPU. Follow the
instructions below to install the Heatsink/Fan:

1. Locate the CPU and its retention

mechanism on the motherboard.

retention mechanism

3. Mount the fan on top of the heatsink.

Press down the fan until its four clips
get wedged in the holes of the reten­tion mechanism.

2. Position the heatsink onto the reten­tion mechanism.

4. Press the two levers down to fasten
the fan. Each lever can be pressed
down in only ONE direction.

levers

2-5

MS-6785 M-ATX Mainboard

5. Connect the fan power cable from the mounted fan to the 3-pin fan power connector
on the board.

fan power cable

2-6

NOTES

Hardware Setup

Memory

The mainboard provides 2 slots for 184-pin DDR SDRAM DIMM
(Double In-Line Memory Module) modules and supports the memory size up
to 2GB. You can install PC2700/DDR333, PC2100/DDR266 or PC1600/
DDR200 modules on the DDR DIMM slots (DIMM 1~2).

DDR DIMM Slots

(DIMM 1~2)

Introduction to DDR SDRAM

DDR (Double Data Rate) SDRAM is similar to conventional SDRAM,
but doubles the rate by transferring data twice per cycle. It uses 2.5 volts as
opposed to 3.3 volts used in SDR SDRAM, and requires 184-pin DIMM mod­ules rather than 168-pin DIMM modules used by SDR SDRAM. High memory
bandwidth makes DDR an ideal solution for high performance PC, worksta­tions and servers.

2-7

MS-6785 M-ATX Mainboard

DIMM Module Combination

Install at least one DIMM module on the slots. Memory modules can be
installed on the slots in any order. You can install either single- or double­sided modules to meet your own needs.

Memory modules can be installed in any combination as follows:

Slot Memory Module Total Memory

DIMM 1
(Bank 0 & 1)
DIMM 2
(Bank 2 & 3)

Maximum System Memory Supported

S/D 64MB~1GB

S/D 64MB~1GB

64MB~2GB

S: Single Side D: Double Side

Installing DDR Modules

1. The DDR DIMM has only one notch on the center of module. The mod-

ule will only fit in the right orientation.

2. Insert the DIMM memory module vertically into the DIMM slot. Then

push it in until the golden finger on the memory module is deeply inserted
in the socket.

MSI Reminds You...

You can barely see the golden finger if the module is properly
inserted in the socket.

3. The plastic clip at each side of the DIMM slot will automatically close.

Volt

Notch

2-8

Hardware Setup

Power Supply

The mainboard supports ATX power supply for the power system. Be­fore inserting the power supply connector, always make sure that all compo­nents are installed properly to ensure that no damage will be caused.

ATX 20-Pin Power Connector: CONN1

This connector allows you to connect to an ATX power supply . To con­nect to the ATX power supply, make sure the plug of the power supply is
inserted in the proper orientation and the pins are aligned. Then push down
the power supply firmly into the connector.

ATX 12V Power Connector: JPW1

This 12V power connector is used to provide power to the CPU.

JPW1

3 4
1

2

JPW1 Pin Definition

PIN SIGNAL

1 GND
2 GND
3 12V
4 12V

CONN1 Pin Definition

PIN SIGNAL

1 3.3V
2 3.3V
3 GND
45V
5 GND
65V
7 GND
8 PW_OK
9 5V_SB
10 12V

11

20

CONN1

PIN SIGNAL

11 3.3V
12 -12V
13 GND
14 PS_ON
15 GND
16 GND
17 GND
18 -5V
19 5V
20 5V

1

10

2-9

MS-6785 M-ATX Mainboard

Back Panel

The back panel provides the following connectors:

Mouse

LAN

IEEE1394

Ports

SPDIF-In

6 Channel

L-Out

MIC

Keyboard

USBCOM A

SPDIF-Out

L-In

Mouse/Keyboard Connector

The mainboard provides a standard PS/2® mouse/keyboard mini DIN
connector for attaching a PS/2® mouse/keyboard. Y ou can plug a PS/2® mouse/
keyboard directly into this connector. The connector location and pin assign­ments are as follows:

Pin Definition

6

4

2

5

3

1

PS/2 Mouse/Keyboard

(6-pin Female)

PIN SIGNAL DESCRIPTION

1 Mouse/Keyboard Data Mouse/Keyboard data
2 NC No connection
3 GND Ground
4 VCC +5V
5 Mouse/Keyboard Clock Mouse/Keyboard clock
6 NC No connection

2-10

Hardware Setup

SPDIF Connectors

The SPDIF connectors privided on the back pannel can be used to con­nect your digital audio equipment.

SPDIF

IN

SPDIF

OUT

Serial Port Connector: COM A

The mainboard offers one 9-pin male DIN connectors as serial port COM
A. This port is a 16550A high speed communication port that sends/receives
16 bytes FIFOs. You can attach a serial mouse or other serial devices directly
to this connector.

1 2 3 4 5

6 7 8 9

9-Pin Male DIN Connector

Pin Definition

PIN SIGNAL DESCRIPTION

1 DCD Data Carry Detect
2 SIN Serial In or Receive Data
3 SOUT Serial Out or Transmit Data
4 DTR Data Terminal Ready)
5 GND Ground
6 DSR Data Set Ready
7 RTS Request To Send
8 CTS Clear To Send
9 RI Ring Indicate

2-11

MS-6785 M-ATX Mainboard

Parallel Port Connector: LPT1

The mainboard provides a 25-pin female centronic connector as LPT. A
parallel port is a standard printer port that supports Enhanced Parallel Port
(EPP) and Extended Capabilities Parallel Port (ECP) mode.

13 1

25

14

Pin Definition

PIN SIGNAL DESCRIPTION

1 STROBE Strobe
2 DATA0 Data0
3 DATA1 Data1
4 DATA2 Data2
5 DATA3 Data3
6 DATA4 Data4
7 DATA5 Data5
8 DATA6 Data6
9 DATA7 Data7
10 ACK# Acknowledge
11 BUSY Busy
12 PE Paper End
13 SELECT Select
14 AUTO FEED# Automatic Feed
15 ERR# Error
16 INIT# Initialize Printer
17 SLIN# Select In
18 GND Ground
19 GND Ground
20 GND Ground
21 GND Ground
22 GND Ground
23 GND Ground
24 GND Ground
25 GND Ground

2-12

Hardware Setup

RJ-45 LAN Jack (Optional)

The mainboard provides one standard RJ-45 jack for connection to Lo­cal Area Network (LAN). You can connect a network cable to the LAN jack.

Pin Definition

PIN SIGNAL DESCRIPTION

1 TDP Transmit Differential Pair

RJ-45 LAN Jack

2 TDN Transmit Differential Pair
3 RDP Receive Differential Pair
4 NC Not Used
5 NC Not Used
6 RDN Receive Differential Pair
7 NC Not Used
8 NC Not Used

USB Connectors

The mainboard provides four UHCI (Universal Host Controller Interface)
Universal Serial Bus roots for attaching USB devices such as keyboard, mouse
or other USB-compatible devices. You can plug USB devices directly into the
connectors.

1 2 3 4

5 6 7 8

USB Ports

USB Port Description

PIN SIGNAL DESCRIPTION

1 VCC +5V
2 -Data 0 Negative Data Channel 0
3 +Data0 Positive Data Channel 0
4 GND Ground
5 VCC +5V
6 -Data 1 Negative Data Channel 1
7 +Data 1 Positive Data Channel 1
8 GND Ground

2-13

MS-6785 M-ATX Mainboard

IEEE1394 Ports

The mainboard provides two IEEE 1394 ports. The mini IEEE1394
port is designed for you to connect the IEEE1394 device with external power.
The standard IEEE1394 port connects to IEEE1394 devices without external
power. The IEEE1394 high-speed serial bus complements USB by providing
enhanced PC connectivity for a wide range of devices, including consumer
electronics audio/video (A/V) appliances, storage peripherals, other PCs, and
portable devices.

IEEE1394 Port

(Standard)

IEEE1394 Port

(Mini)

Audio Port Connectors

Line Out is a connector for Speakers or Headphones. Line In is used for

external CD player, Tape player, or other audio devices. Mic is a connector
for microphones.

Line-Out
(subwoofer speaker)

Line-Out
(rear speakers)

Line-Out
(front speaker)

MIC

Line-In

2-14

Hardware Setup

Connectors

The mainboard provides connectors to connect to FDD, IDE HDD, case,
modem, LAN, USB Ports, IR module and CPU/System/Power Supply F AN.

Floppy Disk Drive Connector: FDD1

The mainboard provides a standard floppy disk drive connector that sup­ports 360K, 720K, 1.2M, 1.44M and 2.88M floppy disk types.

FDD1

2-15

MS-6785 M-ATX Mainboard

Hard Disk Connectors: IDE1 & IDE2

The mainboard has a 32-bit Enhanced PCI IDE and Ultra ATA 33/66/
100/133 controller that provides PIO mode 0~4, Bus Master, and Ultra ATA
33/66/100/133 function. You can connect up to four hard disk drives, CD­ROM, 120MB Floppy (reserved for future BIOS) and other devices.

The Ultra AT A 133 interface boosts data transfer rates between the com­puter and the hard drive up to 133 megabytes (MB) per second. The new
interface is one-third faster than earlier record-breaking Ultra ATA/100 tech­nology and is backwards compatible with the existing Ultra AT A interface.

IDE2

IDE1

IDE1 (Primary IDE Connector)
The first hard drive should always be connected to IDE1. IDE1 can

connect a Master and a Slave drive. You must configure second hard
drive to Slave mode by setting the jumper accordingly.

IDE2 (Secondary IDE Connector)
IDE2 can also connect a Master and a Slave drive.

MSI Reminds You...

If you install two hard disks on cable, you must configure the
second drive to Slave mode by setting its jumper. Refer to the
hard disk documentation supplied by hard disk vendors for
jumper setting instructions.

2-16

Hardware Setup

Fan Power Connectors: CPUFAN1

The CPUFAN1 (processor fan) supports system cooling fan with +12V.
It supports three-pin head connector. When connecting the wire to the
connectors, always take note that the red wire is the positive and should be
connected to the +12V, the black wire is Ground and should be connected to
GND. If the mainboard has a System Hardware Monitor chipset on-board, you
must use a specially designed fan with speed sensor to take advantage of the
CPU fan control.

SENSOR

+12V

GND

CPUFAN1

MSI Reminds You...

Always consult the vendors for proper CPU cooling fan.

2-17

MS-6785 M-ATX Mainboard

CD-In Connector: JVIDEO1

The connector is for CD-ROM video connector.

JVEDIO1

R

GND

L

Front Panel Connector: F_P1

The mainboard provides one front panel connector for electrical con­nection to the front panel switches and LEDs.

2-18

1

8

PS-ON
PWR_LED

HDD_LED

Reset

F_P1

Hardware Setup

Front USB Connector: JUSB1

The mainboard provides one USB 2.0 pin header JUSB1 (optional USB

2.0 bracket available) that is compliant with Intel® I/O Connectivity Design
Guide. USB 2.0 technology increases data transfer rate up to a maximum
throughput of 480Mbps, which is 40 times faster than USB 1.1, and is ideal
for connecting high-speed USB interface peripherals such as USB HDD, dig-
ital cameras, MP3 players, printers, modems and the like.

JUSB1

17 18

JUSB1 Pin Definition

Pin Description Pin Description

1 Power 2 Power
3 D1+ 4 D0+
5 D1- 6 D0­7 GND 8 GND
9 SGND 10 SGND
11 GND 12 GND
13 D3- 14 D2­15 D3+ 16 D2+
17 Power 18 Power

2

1

2-19

MS-6785 M-ATX Mainboard

Joystick/Game Connector: CN8 (Optional)

You can connect a joystick or game pad to this connector.

CN8

1

2

2-20

11

12

J9 Pin Definition

Pin Description Pin Description

1 FVCC5 (power) 2 Key pin
3 RXD 4 GP4
5 GP5 6 GP6
7 GP7 8 GP2
9 GP1 10 GP0
11 GP3 12 TXD

Hardware Setup

SPDIF Connector: JSPDIF1

The connector is used to connect an optional bracket for SPDIF (Sony &
Philips Digital Interconnect Format) digital audio transmission.

4

1

36

JSPDIF1

JSPDIF1 Pin Definition

Pin Description Pin Description

1 VCC5 2 VCC3
3 SPDIF-O 4 NC
5 GND 6 SPDIF-I

2-21

MS-6785 M-ATX Mainboard

Front Panel Audio Connector: JAUDIO1

The JAUDIO1 front panel audio connector allows you to connect front
panel audio devices if available.

2-22

2

1

JAUDIO1 Pin Definition

Pin Description Pin Description

1 Speaker_R 2 Front_R
3 Speaker_L 4 Front_L
5 GND 6 GND
7 MIC_IN 8 Line_Next_R
9 MIC_IN_S 10 Line_Next_L

MSI Reminds You...

If you don’t want to connect to the front audio
header, pins 1 & 2, 3 & 4 have to be jumpered in
order to have signal output directed to the rear
audio ports. Otherwise, the Line-Out connector on
the back panel will not function.

JAUDIO1

2

1

3

10

9

4

Hardware Setup

IEEE 1394 Connector: J9 (Optional)

The mainboard provides one IEEE1394 connector with housing that

allows you to connect optional IEEE 1394 ports.

J9

1

2

9

10

Pin Definition

PIN SIGNAL PIN SIGNAL

1 IEGND 2 GND
3 TPA0- 4 TPA0+
5 Power 6 Power
7 TPB0+ 8 TPB0­9 GND 10 IEGND

2-23

MS-6785 M-ATX Mainboard

Print Port: JLPT

This mainboard provides a pin header, JLPT, for connecting a printer.

26 25

12

JLPT

Pin Definition

PIN DESCRIPTION

1 STROBE
2DATA0
3DATA1
4DATA2
5DATA3
6DATA4
7DATA5
8DATA6
9DATA7
10 ACK#
11 BUSY
12 PE
13 SELECT
14 AUTO FEED#
15 ERR#
16 INIT#
17 SLIN#
18 GND
19 GND
20 GND
21 GND
22 GND
23 GND
24 GND
25 GND
26 NC

2-24

Hardware Setup

Jumpers

The motherboard provides the following jumpers for you to set the
computer’s function. This section will explain how to change your
motherboard’s function through the use of jumpers.

Clear CMOS Jumper: JBAT1

There is a CMOS RAM on board that has a power supply from external
battery to keep the data of system configuration. With the CMOS RAM, the
system can automatically boot OS every time it is turned on. If you want to
clear the system configuration, use the JBAT1 (Clear CMOS Jumper ) to clear
data. Follow the instructions below to clear the data:

1

JBAT1

1

Keep Data Clear Data

313

MSI Reminds You...

You can clear CMOS by shorting 2-3 pin while the system is off.
Then return to 1-2 pin position. Avoid clearing the CMOS while
the system is on; it will damage the mainboard.

2-25

MS-6785 M-ATX Mainboard

Slots

The motherboard provides one AGP slot and three 32-bit Master PCI
bus slots.

AGP Slot

PCI Slots

AGP (Accelerated Graphics Port) Slot

The AGP slot allows you to insert the AGP graphics card. AGP is an
interface specification designed for the throughput demands of 3D graphics.
It introduces a 66MHz, 32-bit channel for the graphics controller to directly
access main memory. The onboard AGP slot supports up to 8X AGP card.

PCI (Peripheral Component Interconnect) Slots

The PCI slots allow you to insert the expansion cards to meet your needs.
When adding or removing expansion cards, make sure that you unplug the
power supply first. Meanwhile, read the documentation for the expansion card
to make any necessary hardware or software settings for the expansion card,
such as jumpers, switches or BIOS configuration. The second PCI slot (in

BLUE color) supports 2 master devices.

2-26

Hardware Setup

PCI Interrupt Request Routing

The IRQ, acronym of interrupt request line and pronounced I-R-Q, are
hardware lines over which devices can send interrupt signals to the
microprocessor. The PCI IRQ pins are typically connected to the PCI bus INT
A# ~ INT D# pins as follows:

Order 1 Order 2 Order 3 Order 4
PCI Slot 1 INT A# INT B# INT C# INT D#
PCI Slot 2 INT B# INT C# INT D# INT A#
PCI Slot 3 INT C# INT D# INT A# INT B#

2-27