MSI P4m900m3l Manual

							3-15 BIOS Setup Power Button Mode
This feature allows users to configure the Power Button function. Settings are:
[Power Off]The power button functions as a normal power-on/-off button.
[Suspend]When you press the power button, the computer enters the
suspend/sleep mode, but if the button is pressed for more
than four seconds, the computer is turned off.  Restore on AC/Power Loss
This setting specifies whether your system will reboot after a power failure or
interrupt occurs. Available settings are:
[Power Off]Leaves the computer in the power off state.
[Power On]Leaves the computer in the power on state.
[Last State]Restores the system to the previous status before power
failure or interrupt occurred.
Wakeup Event Setup
Press  to enter sub-menu. Resume On KBC
The item specifies how the system will be awakened from power saving mode
when input signal of the keyboard is detected. Wake-Up Key
This setting only works Resume On KBC is set to [Enabled]. This setting speci-
fies how the system will be awakened from power saving mode when input
signal of the keyboard is detected. Resume On PS/2 Mouse
The setting determines whether the system will be awakened from what power
saving modes when input signal of the PS/2 mouse is detected. Resume On Lan
The item specifies how the system will be awakened from power saving mode
when input signal of the Lan is detected. Resume On RTC Alarm
This is used to enable or disable the feature of booting up the system on a
scheduled time/date from the S3, S4, and S5 state. USB Device Wakeup function
This setting allows USB device wake up the system from S3 state. PCI Express Wakeup
The item specifies how the system will be awakened from power saving mode
when input signal of the PCI Express is detectedCH3 BIOS Setup.p65  2006/9/15, 下午 02:1415 
						

							MS-7255 Mainboard
3-16PNP/PCI Resource Management Clear NVRAM
The NVRAM (Non-volatile Random Access Memory) is where the BIOS stores re-
source information for both PNP and non-PNP devices in a bit string format. When the
item is set to [Yes], the system will reset NVRAM right after the system is booted up
and then set the setting of the item back to [No] automatically. PCI Latency Timer
This item controls how long each PCI device can hold the bus before another takes
over. When set to higher values, every PCI device can conduct transactions for a
longer time and thus improve the effective PCI bandwidth. For better PCI performance,
you should set the item to higher values. PCI Slot1~2 IRQ Preference
These items specify the IRQ line for each PCI slot. This section describes configuring the PCI bus system and PnP (Plug & Play) feature.
PCI, or Peripheral Component Interconnect, is a system which allows I/O devices to
operate at speeds nearing the speed the CPU itself uses when communicating with
its special components. This section covers some very technical items and it is
strongly recommended that only experienced users should make any changes to the
default settings.CH3 BIOS Setup.p65  2006/9/15, 下午 02:1416 
						

							3-17 BIOS Setup IRQ Resources Setup
The items are adjustable only when Resources Controlled By is set to Manual.
Press  and you will enter the sub-menu of the items. IRQ Resources list IRQ
3/4/5/7/9/10/11/12/14/15 for users to set each IRQ a type depending on the type of
device using the IRQ. Settings are:
AvailableFor Plug & Play compatible devices designed for PCI bus
architecture.
ReservedThe IRQ will be reserved for further request. DMA Resources Setup
Press  and you will enter the sub-menu of the items.DMA Resources  0/1/3/5/
6/7 for setting determine if BIOS should remove a DMA from the available DMAs
passed to devices that are configurable by the system BIOS. The available DMA pool
is determined by reading the NVRAM. If more DMAs must be removed from the pool,
the end user can reserve the DMA.CH3 BIOS Setup.p65  2006/9/15, 下午 02:1417 
						

							MS-7255 Mainboard
3-18H/W MonitorThis section shows the status of your CPU, fan, overall system status, etc. Monitor
function is available only if there is hardware monitoring mechanism onboard. CPU Shutdown Temperature
If the CPU temperature reaches the upper limit preset in this setting, the system will be
shut down automatically. This helps you to prevent the CPU overheating problem.
This item is available only when your OS supports this function, such as Windows
ME/XP. Chassis Intrusion
The field enables or disables the feature of recording the chassis intrusion status and
issuing a warning message if the chassis is once opened. To clear the warning
message, set the field to [Reset]. The setting of the field will automatically return to
[Enabled] later. System/CPU Temperature, CPU/SYSFAN Speed, Vcore, 5VIN, 12VIN, 3.3V,,
3VBS, VBAT
These items display the current status of all of the monitored hardware devices/
components such as CPU voltages, temperatures and all fans’ speeds.CH3 BIOS Setup.p65  2006/9/15, 下午 02:1418 
						

							3-19 BIOS SetupCell MenuThe items here includes some important settings of CPU and PCI functions. Adjust DDR Voltage (V)
Adjusting the DDR voltage can increase the DDR speed.  Any changes made to this
setting may cause a stability issue, so changing the DDR voltage for long-term
purpose is NOT recommended. Adjust NB Voltage (V)
NorthBridge voltage is adjustable in the field, allowing you to increase the perfor-
mance of your NorthBridge when overclocking, but stability may be affected.Important
Change these settings only if you are familiar with the chipset.Important
The settings shown in different color in CPU Voltage, DDR Voltage and NB
Voltage help to verify if your setting is proper for your system.
Gray:Default setting.
White:Safe setting.
Yellow:High performance setting.
Red:Not recommended setting and the system may be unstable.
Changing CPU Voltage, DDR Voltage and NB Voltage may result in the insta-
bility of the system; therefore, it is NOT recommended to change the default
setting for long-term usage.CH3 BIOS Setup.p65  2006/9/15, 下午 02:1419 
						

							MS-7255 Mainboard
3-20 Spread Spectrum
When the motherboard’s clock generator pulses, the extreme values (spikes) of the
pulses creates EMI (Electromagnetic Interference). The Spread Spectrum function
reduces the EMI generated by modulating the pulses so that the spikes of the pulses
are reduced to flatter curves. If you do not have any EMI problem, leave the setting at
[Disabled] for optimal system stability and performance. But if you are plagued by EMI,
select the desired range for EMI reduction. Remember to disable Spread Spectrum
function if you are overclocking, because even a slight jitter can introduce a tempo-
rary boost in clock speed which may just cause your overclocked processor to lock
up. Adjust CPU FSB Frequency
This item allows you to select the CPU Front Side Bus clock frequency (in MHz) and
overclock the processor by adjusting the FSB clock to a higher frequency. Adjust PCI Express Frequency
This item allows you to select the PCI Express frequency (in MHz). Adjust PCI Frequency
This item allows you to select the PCI frequency (in MHz). In default this value will
change automatically in accordance with the setting of Adjust CPU FSB Frequency.
However, you may adjust the desired fixed PCI frequency you like by using the 
&  key. Auto Disable PCI Clock
This item is used to auto disable the PCI slots. When set to [Enabled], the system will
remove (turn off) clocks from empty PCI slots to minimize the electromagnetic inter-
ference (EMI).CH3 BIOS Setup.p65  2006/9/15, 下午 02:1420 
						

							3-21 BIOS SetupLoad Optimized Defaults
The two options on the main menu allow users to restore all of the BIOS settings to
the default Fail-Safe or Optimized values. The Optimized Defaults are the default
values set by the mainboard manufacturer specifically for optimal performance of the
mainboard. The Fail-Safe Defaults are the default values set by the BIOS vendor for
stable system performance.
When you select Load Fail-Safe Defaults, a message as below appears:Pressing Y loads the BIOS default values for the most stable, minimal system
performance.
When you select Load Optimized Defaults, a message as below appears:Pressing Y loads the default factory settings for optimal system performance.CH3 BIOS Setup.p65  2006/9/15, 下午 02:1421 
						

							MS-7255 Mainboard
3-22BIOS Setting Password
When you select this function, a message as below will appear on the screen:Type the password, up to 6 characters in length, and press . The password
typed now will replace any previously set password from CMOS memory. You will be
prompted to confirm the password. Retype the password and press . You
may also press  to abort the selection and not enter a password.
To clear a set password, just press  when you are prompted to enter the
password. A message will show up confirming the password will be disabled. Once
the password is disabled, the system will boot and you can enter Setup without
entering any password.
When a password has been set, you will be prompted to enter it every time you try to
enter Setup. This prevents an unauthorized person from changing any part of your
system configuration.CH3 BIOS Setup.p65  2006/9/15, 下午 02:1422 
						

							Appendix. Using 4- or 6-Channel
Audio Function Chapter 5. nVidia RAID Intro-
ductionThe Southbridge VT8237 provides a hybrid solution that combines two
independent SATA ports for support of up to two Serial ATA (Serial ATA
RAID) drives.
Serial ATA (SATA) is the latest generation of the ATA interface. SATA
hard drives deliver blistering transfer speeds of up to 150MB/sec.
Serial ATA uses long, thin cables, making it easier to connect your drive
and improving the airflow inside your PC.
The key features of VT8237 SATA RAID are:
1.Dual independent ATA channels and maximum connection of
two SATA hard disk  drives allowed.
2.Supports RAID 0 or RAID 1.
3.4 KB to 64 KB striping block size support.
4.Bootable disk or disk array support.
5.Windows-based RAID configure and management software
tool.(Compatible with BIOS)
6.Supports hot-swap failed disk drive in RAID 1 array.
7.Microsoft Windows 98, Me, 2000, XP operating systems
support.
8.Event log for easy troubleshooting.VIA VT8237 SATA
RAID Introduction Appendix AAppendix VT8237RAID.p65  2006/9/15, 下午 02:141 
						

							MS-7255 Mainboard
A-2Introduction
This section gives a brief introduction on the RAID-related background knowledge and
a brief introduction on VIA SATA RAID Host Controller.  For users wishing to install their
VIA SATA RAID driver and RAID software, proceed to Driver and RAID Software
Installation section.
RAID Basics
RAID (Redundant Array of Independent Disks) is a method of combining two or more
hard disk drives into one logical unit. The advantage of an Array is to provide better
performance or data fault tolerance. Fault tolerance is achieved through data redundant
operation, where if one drives fails, a mirrored copy of the data can be found on
another drive. This can prevent data loss if the operating system fails or hangs. The
individual disk drives in an array are called “members”. The configuration information of
each member is recorded in the “reserved sector” that identifies the drive as a member.
All disk members in a formed disk array are recognized as a single physical drive to the
operating system.
Hard disk drives can be combined together through a few different methods. The
different methods are referred to as different RAID levels.  Different RAID levels
represent different performance levels, security levels and implementation costs. The
RAID levels which the VIA VT8237 SATA RAID Host Controller supports are RAID 0 and
RAID 1. The table below  briefly introduced these RAID levels.
RAID Level No. of Drives Capacity Benefits RAID 0 
(Striping) 2  Smallest size * 2 Highest performance without 
data protection RAID 1 
(Mirroring) 2 Smallest size Data protection   RAID 0 (Striping)
RAID 0 reads and writes sectors of data interleaved between multiple drives.  If
any disk member fails, it affects the entire array. The disk array data capacity is equal
to the number of drive members times the capacity of the smallest member.  The striping
block size can be set from 4KB to 64KB.  RAID 0 does not support fault tolerance.
RAID 1 (Mirroring)
RAID 1 writes duplicate data onto a pair of drives and reads both sets of data in
parallel.  If one of the mirrored drives suffers a mechanical failure or does not respond,
the remaining drive will continue to function.  Due to redundancy, the drive capacity of
the array is the capacity of the smallest drive.  Under a RAID 1 setup, an extra drive
called the .spare drive. can be attached.  Such a drive will be activated to replace a
failed drive that is part of a mirrored array.  Due to the fault tolerance, if any RAID 1 drive
fails, data access will not be affected as long as there are other working drives in the
array.Appendix VT8237RAID.p65  2006/9/15, 下午 02:142