Resource Allocation. Part IV

VGA Share Memory Size (Frame Buffer Size)

This parameter allows setting a size of operating memory which will be allocated for operation of integrated video adapter.

Possible values: 8M, 16M, 32M, 64M, 128M, 256M, 512M – a size of allocated memory in Mbytes. The amount of memory available for operating system and some applications will be decreased by appropriate value.

PCI Latency Timer

This parameter sets the time delay when the control over PCI-bus is transmitted from one device which operates in Bus Master Mode to another.

Possible values – 32, 64, 96, 128, 160, 192, 224, 248. The values 32 or 64 are set by default. As a rule, such value corresponds to maximum system capacity.

PCI/VGA Palette Snoop (Palette Snooping)

This parameter sets a special mode that corrects VGA palette using additional video devices, for example MPEG-encoder.

If there are some problems with operation of such devices, set the value “Enabled (On)” and for all other cases select “Disabled (Off).

Maximum Payload Size

Some motherboards with PCI Express-bus have got such parameter. It sets a maximum size of data package transmitted via this bus.

Possible values – 128, 256, 512, 1024, 2048, 4096. They define a maximum size of data package in bytes. A value 4096 is set by default; it should not be changed without any necessity while ensuring the maximum capacity of PCI Express.

Resource Allocation. Part III

DMA x Assigned to

If the manual resource allocation is set (Resources Controller By), some versions of BIOS allow reserving DMA channels for outdated devices. The possible values for these parameters are similar to those in “IRQ x Assigned to”.

PIRQ x Use IRQ No, INT Pin x Assignment

These parameters allow setting the interruption assignment between PCI- and AGP-devices manually using programming interruption queries (PIRQ).

The interruption assignment using PIRQ is a relatively difficult task and its use is rather doubtful so always select the value “Auto”.

PCI Slot x IRQ (Slot x)

This parameter sets a certain interruption for a particular PCI-slot and it is a simplified version of “PIRQ x Use IRQ No”. Almost always set Auto.

Init Display First (Primary Graphic’s Adapter, Initiate Graphic Adapter)

A set of parameters for setting video adapter and several other devices can be found in a section “PnP/PCI Configurations”. This parameter allows selecting the first video adapter and its correct value slightly speeds up the booting.

Possible values:

  • PCI – first of all a system tries to identify the video adapter installed in PCI-slot;
  • AGP – AGP-adapter will be initialized first;
  • Onboard – firstly, an adapter integrated into a motherboard will be identified;
  • PCI Express (PCIE, PEG) – PCI Express adapter will be the first.

In some versions of BIOS, an inquiry order of adapters can be set, for example PCI/AGP and AGP/PCI.

Resource Allocation. Part II

Reset Configuration Data (Force Update ESCD)

This parameter allows forcibly updating data of system configuration and resource distribution table (ESCD). In some cases such action allows “revitalizing” the system that refuses to boot normally after adding or deletion of expansion boards.

Possible values:

  • Disabled (No) – ESCD cleaning is prohibited (this value corresponds to normal computer operation);
  • Enabled (Yes) – resource distribution tables will be cleaned and rebuilt during the next system rebooting. Then a value Disabled will be automatically set.


Assign IRQ for VGA (Allocate IRQ to PCI VGA)

This parameter enables or disables interruption assignment (IRQ) for video adapter. The value “Enabled (On)” is set (and recommended) by default and the interruption will be allocated.


Assign IRQ for USB

This parameter enables (the value “Enabled (On) – by default) or disables (Disabled (Off)) interruption assignment (IRQ) for USB-devices.


Resources Controlled By

This parameter defines the method of allocation of interruptions (IRQ) and channels of direct memory access (DMA).

Possible values:

  • Auto (ESCD) – resources are allocated automatically (this value is by default); it is recommended if there are no outdated expansion boards in the system;
  • Manual – resources are allocated manually using the parameters “IRQ x Assigned to” and “DMA x Assigned to”.


IRQ x Assigned to

If the method of interruption allocation is set manually in “Resources Controlled By”, the settings for separate interruption can be changed. You may select one of two values:

  • PCI/ISA PnP (PCI Device) – automatic assignment of interruptions for one of devices and Plug and Play support (this value is set by default);
  • Legacy ISA (Manual, Reserved) – an interruption will be reserved for ISA-board.

Resource Allocation. Part I

It is necessary to allocate the resources of a motherboard for normal operation of various devices: interruption (IRQ), channels of direct memory access (DMA), input/output addresses or accessed memory scopes. Most versions of BIOS have special section “PnP/PCI Configurations” which contains resource settings.


If you set these values by default, the system will automatically allocate all resources according to Plug and Play standard. Manual setting may be required to connect some non-standard or outdated devices. The necessity of manual resource setting is very rare so the section “PnP/PCI Configurations” is considerably reduced in modern motherboards and it may have two or three particularly important parameters.

Plug and Play OS (PnP OS Installed)

This parameter defines what will allocate the resources – BIOS or operating system.

Possible values:

  • Yes – BIOS configures those devices which are necessary for booting while operating system sets the rest ones but it must support Plug and Play;
  • No – all devices are set and all resources are allocated by BIOS.

Modern versions of BIOS control the devices using the function “ACPI”. If BIOS complies with this standard, operating system will configure them even with a value No.

Network Connection Testing

A lot of modern versions of BIOS have built-in diagnostic tools of network connection. The motherboards by ASUS have special sections “LAN Cable Status” or “AI Net2” for this which can be located in “Advanced” or “Tools”. The diagnostic utility in motherboards by Gigabyte starts using the command “SMART LAN” in the section “Integrated Peripherals”. The similar tools can also be found in motherboards by other manufacturers.


A twisted-pair cable consists of four pairs of wires; the status of each of them will be displayed in Status: Open – a pair is not connected or it has a failure; Normal – the status of a pair is normal and Short – a pair is shorted. A desired cable length in meters is displayed in “Length” before failure or interruption.


The wire pairs 4-5 and 7-8 are not used with the network adapter speed of 10/100 Mbt/s so their status may be defined as Open or Short.

If the value Enabled is set for “POST Check LAN Cable” parameter, the network testing will be implemented during every computer booting. In case of failure, the booting will be stopped and a certain warning will be displayed on the screen. This is useful in those cases when the server availability is necessary for computer operation. Otherwise, it is better to set Disabled for this parameter in order not to increase the booting time.


Southern bridges of modern chipsets may support a huge amount of various peripherals. Each of them has its own parameter of BIOS with the help of which it may be turned off by setting a value “Disabled (Off)” and turned on by setting a value “Enabled (On)” or “Auto”.

This is the list of these parameters for the most popular peripherals:

  • AC97 Audio (Audio Controller, Onboard Audio Chip, Azalia Codec) – controls the functioning of integrated audio adapter;
  • Onboard FDC Controller (Onboard Floppy Controller) – turns on or off a built-in floppy controller;
  • Onboard LAN Control (MAC LAN) – turns on or off an integrated network controller. The parameter “Onboard LAN Option ROM (Onboard LAN Boot ROM)” may be also available; it enables or disables the remote booting from the network;
  • Onboard IEEE 1394 Controller (IEEE 1394) – turns on or off IEE controller 1394 (FireWire) integrated into the motherboard;
  • Onboard Game/MIDI Port – controls the operation of built-in game or MIDI port. The parameters for setting the resources of indicated ports may be also available; it is better to leave their values by default;
  • Onboard Infrared Port – controls the operation of built-in infrared port. If this parameter is on, the additional settings are usually available and their values should not be changed unless necessary.

Parallel and Serial Ports

The settings of input/output ports can be addressed in a separate subsection called “Onboard I/O Chip Setup”, “Super I/O Device”, “I/O Devices” or similar to it.

Onboard Serial Port 1/2 (COM Port 1/2)

This parameter switches on or off the first or the second serial port and also specifies the interruption and input/output address for it. Possible values:

  • Auto – serial port is off. The resources are distinguished automatically for it (recommended value);
  • 3F8/IRQ4, 2F8/IRQ3, 3E8/IRQ4, 2E8/IRQ3 – the input/output address and interruption for a port are selected from the proposed list;
  • Disabled (Off) – a serial port is off; it does not use any resources.


Onboard Parallel Port (Parallel Port)

This parameter adjusts the resources of the built-in parallel port through which a printer and other devices are connected.

Possible values:

  • 378/IRQ7 (by default), 3BC/IRQ7, 278/IRQ5 – the input/output address and interruption used by a parallel port;
  • Disabled (Off) – the port is off and it does not use any resources.

Some versions of BIOS use the separate parameters “Parallel Port Address” and “Parallel Port IRQ” instead of this parameter to set the input/output address and interruption accordingly.

Parallel Port Mode (Onboard Parallel Mode, Parallel Port Type)

This parameter selects an operating mode of built-in parallel port.

Possible values:

  • Normal (SPP) – a standard operating mode of parallel port (set this value when a device does not operate properly in much faster modes);
  • ECP, EPP or ECP+EPP – a port operates in one of fast modes (ECP or EPP). In this case the additional parameters for installing these modes may be available: EPP Mode Select (EPP Version) – installing the version of EPP (1.9 is recommended) and ECP Mode Use DMA (ECP Mode DMA Channel) – a number of DMA channel (DMA3 is recommended).


Nowadays USB is the generally accepted standard for connection of various internal devices to the system block. Modern computers may have six, eight or more USB-connectors and they may be located on the front, back or side panel of the computer.

USB Controller (OnChip USB Controller, OnChip EHCI Controller)

This parameter switches on (a value Enabled (On)) or off (a value Disabled (Off)) the built-in USB-controller. As USB-devices are rather popular nowadays, there are no serious reasons to select the second value.

USB 2.0 Controller (USB 2.0 Support)

This parameter allows listing a version of the protocol (USB 1.1 or USB 2.0) which USB-controller will operate with.

Possible values:

  • Enabled (On) – USB 2.0 protocol is used which provides much higher speed of data transmission;
  • Disabled (Off) – USB 1.1 protocol is used. This value may be selected only if there are some problems in functioning of devices with USB 2.0 protocol.

USB Legacy Support (USB Keyboard Support Via)

This parameter enables or disables BIOS support of USB-devices and is important in case of USB-keyboard usage.

Possible values:

  • Enabled (On, BIOS) – the support of USB-devices at the level of BIOS is allowed. This value must be set only if a computer uses USB-keyboard or the other devices necessary for Windows booting;
  • Disabled (Off, OS) – BIOS support of USB-devices is off. This value is recommended to be set if USB-devices are used only after Windows booting.

USB-Mouse Support

This parameter switches on the support of USB-mouse at a level of BIOS and it is similar to the previous parameter “USB Keyboard Support Via”. It must be switched on if USB-mouse is necessary in such operating systems as MS-DOS.

Serial ATA and RAID Controllers. Part III

SATA Port 0/2 Set to (SATA Port 1/3 Set to, SATA Port)

These parameters indicate which if IDE channels will be used by SATA-disks, and are set automatically depending on the value of the parameter “PATA IDE Mode”.

SATA 1/2 (SATA Port 1/2)

These parameters control an integrated controller Serial ATA, responsible for operation of SATA1 and SATA2.

Possible values:

  • Enabled (On, Auto) – the selected SATA port is on;
  • Disabled (Off, Not Installed) – the port is off.

A similar parameter “SATA3/4” turns on and off SATA3 and SATA4.

IDE SATA RAID Function (RAID Function, RAID Enabled)

This parameter turns on (a value “Enabled (On)”) or off (a value “Disabled (Off)”) an integrated RAID-controller.

Except RAID controllers integrated into the southern chipset bridge, many motherboards have additional RAID controllers of other developers. To turn on such RAID controller in BIOS, use a special parameter with one of the following names:

□ VIA SATA Raid Utility;

□ Onboard Sil3114 RAID;

□ Onboard Promise Controller;

□ JMicron SATA/PATA Controller;

□ Marvell SATA Controller;

□ Intel RAID Technology.

After turning on the RAID controller, the additional parameters may occur here for including some disks in RAID-array (SATA 1/2/3/4 RAID) and more accurate controller setting.


For the next setting of RAID-array, use a utility of RAID setting which is usually described in a manual for the motherboard.

Serial ATA and RAID Controllers. Part II

Onboard IDE Operate Mode

This parameter is similar to the previous one and allows selecting the compatible mode of SATA and IDE controllers.

Possible values:

  • Compatible Mode – a compatible mode with operating systems MS-DOS, Windows 9x/NT4.0;
  • Enhanced Mode – an advanced mode which is recommended for Windows 2000/XP/2003. In this case an additional parameter “Enhanced Mode Support On” may be available for setting this mode.

IDE Port Settings

This parameter was designed for additional configuration of SATA and IDE drives with selected compatible mode and outdated operating systems.

Possible values:

  • Primary, P-ATA+S-ATA – IDE-drives connected to the primary channel and also SATA-disks are used here;
  • Secondary, P-ATA+S-ATA – IDE-drives connected to the secondary channel and also SATA-disks are used here;
  • P-ATA Ports Only – only IDE-drives are used here; SATA-ports are disconnected.


This parameter is similar to the previous one and is suitable for those motherboards where a chipset supports only one channel for the connection of usual IDE-disks.

Possible values:

  • 1 Master/Slave, Secondary IDE2 – IDE-disks will have the marking “Secondary Master” and “Secondary Slave”;
  • Ch.0 Master/Slave, Primary IDE1 – IDE-disks will have the marking “Primary Master” and “Primary Slave”.