A typical north/southbridge layout

Intel 82801BA ICH2 southbridge, often used on Pentium III and early Pentium 4 motherboards.

The Southbridge, also known as the I/O Controller Hub (ICH), is a chip that implements the "slower" capabilities of the motherboard in a northbridge/southbridge chipset computer architecture. The southbridge can usually be distinguished from the northbridge by not being directly connected to the CPU. Rather, the northbridge ties the southbridge to the CPU. Image File history File links Northsouthbridge. ... Image File history File links Size of this preview: 745 × 600 pixelsFull resolution (1959 × 1577 pixel, file size: 3. ... Image File history File links Size of this preview: 745 × 600 pixelsFull resolution (1959 × 1577 pixel, file size: 3. ... Intel Corporation (NASDAQ: INTC, SEHK: 4335), founded in 1968 as Integrated Electronics Corporation, is an American multinational corporation that is best known for designing and manufacturing microprocessors and specialized integrated circuits. ... Pentium III logo The Pentium III is an x86 (more precisely, an i686) architecture microprocessor by Intel, introduced on February 26, 1999. ... The Pentium 4[1] brand refers to Intels mainstream desktop and mobile single-core CPUs (introduced on November 20, 2000[2]) with the seventh-generation NetBurst architecture, which was the companys first all-new design since the Intel P6 of the Pentium Pro branded CPUs of 1995. ... Energy Input: The energy placed into a reaction. ... I/O CONTROLLER Hub (ICH) is the name for the microchip Intel 82801, which works as southbridge on motherboards with Intel chipsets (Intel Hub Architecture). ... A motherboard is the central or primary circuit board making up a complex electronic system, such as a modern computer. ... This article or section does not cite any references or sources. ... It has been suggested that Homebrew CPU be merged into this article or section. ...

Overview

Because the southbridge is further removed from the CPU, it is given responsibility for the slower devices on a typical microcomputer. A particular southbridge will usually work with several different northbridges, but these two chips must be designed to work together; there is no industry-wide standard for interoperability between different core logic chipset designs. Traditionally this interface between northbridge and southbridge was simply the PCI bus, however since this created a performance bottleneck, most current chipsets use a different (often proprietary) interface with higher performance. The Commodore 64 was one of the most popular microcomputers of its era, and is the best selling home computer of all time. ...

Etymology

The name is derived from drawing the architecture in the fashion of a map. The CPU would be at the top of the map at due north. The CPU would be connected to the chipset via a fast bridge (the northbridge) located north of other system devices as drawn. The northbridge would then be connected to the rest of the chipset via a slow bridge (the southbridge) located south of other system devices as drawn. This article or section does not cite any references or sources. ...

Functionality

The functionality found on a contemporary southbridge includes:

• PCI bus. The PCI bus support includes the traditional PCI specification, but may also include support for PCI-X and PCI Express.
• ISA bus or LPC Bridge. Though the ISA support is rarely utilized, it has interestingly managed to remain an integrated part of the modern southbridge. The LPC Bridge provides a data and control path to the Super I/O (the normal attachment for the keyboard, mouse, parallel port, serial port, IR port, and floppy controller) and FWH (firmware hub which provides access to BIOS flash storage).
• SPI bus. The SPI bus is a simple serial bus mostly used for firmware (e.g., BIOS) flash storage access.
• SMBus. The SMBus is used to communicate with other devices on the motherboard (e.g. system fans).
• DMA controller. The DMA controller allows ISA or LPC devices direct access to main memory without needing help from the CPU.
• Interrupt controller. The interrupt controller provides a mechanism for attached devices to get attention from the CPU.
• IDE (SATA or PATA) controller. The IDE interface allows direct attachment of system hard drives.
• Real Time Clock. The real time clock provides a persistent time account.
• Power management (APM and ACPI). The APM or ACPI functions provide methods and signaling to allow the computer to sleep or shut down to save power.
• Nonvolatile BIOS memory. The system CMOS, assisted by battery supplemental power, creates a limited non-volatile storage area for system configuration data.
• AC97 or Intel High Definition Audio sound interface

Optionally, the southbridge will also include support for Ethernet, RAID, USB, audio codec, and FireWire. Rarely, the southbridge may also include support for the keyboard, mouse, and serial ports, but normally these devices are attached through another device referred to as the Super I/O. 64-bit PCI expansion slots inside a Power Macintosh G4 The Peripheral Component Interconnect, or PCI Standard (in practice almost always shortened to PCI), specifies a computer bus for attaching peripheral devices to a computer motherboard. ... For other meanings of PCI, see PCI (disambiguation). ... PCI Express (formerly known as 3GIO for 3rd Generation I/O, not to be mistaken with PCI-X) is an implementation of the PCI computer bus that uses existing PCI programming concepts and communications standards, but bases it on a much faster serial communications system. ... This article does not cite any references or sources. ... The Low Pin Count bus, or LPC bus, is used on PC-style personal computers to connect low-bandwidth devices to the CPU, such as the boot ROM, the legacy I/O devices (behind a Super I/O chip), and audio controllers. ... Super I/O is the name given to a class of I/O controller integrated circuits that began to be used on personal computer motherboards in the late 1980s. ... Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. ... A microcontroller, like this PIC18F8720 is controlled by firmware stored inside on FLASH memory In computing, firmware is a computer program that is embedded in a hardware device, for example a microcontroller. ... This article does not cite any references or sources. ... A USB flash drive. ... The Serial Peripheral Interface Bus or SPI bus is a very loose standard for controlling almost any digital electronics that accepts a clocked serial stream of bits. ... A microcontroller, like this PIC18F8720 is controlled by firmware stored inside on FLASH memory In computing, firmware is a computer program that is embedded in a hardware device, for example a microcontroller. ... This article does not cite any references or sources. ... A USB flash drive. ... The System Management Bus (abbreviated to SMBus or SMB) is a simple two-wire bus used for communication with low-bandwidth devices on a motherboard, especially power related chips such as a laptops rechargeable battery subsystem (see Smart Battery Data). ... Direct memory access (DMA) is a feature of modern computers that allows certain hardware subsystems within the computer to access system memory for reading and/or writing independently of the central processing unit. ... Primary storage is a category of computer storage, often called main memory. ... A Programmable Interrupt Controller (PIC) is a device which allows priority levels to be assigned to its interrupt outputs. ... ATA cables: 40 wire ribbon cable top, 80 wire ribbon cable bottom Advanced Technology Attachment (ATA) is a standard interface for connecting storage devices such as hard disks and CD-ROM drives inside personal computers. ... Typical hard drives of the mid-1990s. ... A real-time clock (RTC) is a computer clock (most often in the form of an integrated circuit chip) that keeps track of the current time even when the computer is turned off. ... APM can also stand for Automatic People Mover. ... The Advanced Configuration and Power Interface (ACPI) specification is an open industry standard first released in December 1996 developed by HP, Intel, Microsoft, Phoenix and Toshiba that defines common interfaces for hardware recognition, motherboard and device configuration and power management. ... Nonvolatile BIOS memory refers to the memory on a personal computer motherboard containing BIOS settings and sometimes the code used to initialize the computer and load the operating system. ... Static CMOS Inverter Complementary metal–oxide–semiconductor (CMOS) (see-moss, IPA: ), is a major class of integrated circuits. ... Non-Volatile Random Access Memory (NVRAM) is a computer memory chip which will not lose its information when the power is lost. ... AC97 (short for Audio Codec 97) is Intel Corporations Audio Codec standard developed by the Intel Architecture Labs in 1997, and used mainly in motherboards (also known as on-board or integrated), modems, and sound cards. ... Intel High Definition Audio (IHD or Azalia) refers to the specification released by Intel in 2004 for delivering high-definition audio that is capable of playing back more channels at higher quality than previous integrated audio codecs like AC97. ... Ethernet is a large, diverse family of frame-based computer networking technologies that operate at many speeds for local area networks (LANs). ... In computing, a redundant array of inexpensive disks, also later known as redundant array of independent disks (commonly abbreviated RAID) is a system which uses multiple hard drives to share or replicate data among the drives. ... A USB Series “A” plug, the most common USB plug Universal Serial Bus (USB) is a serial bus standard to interface devices. ... An audio codec is a computer program that compresses/decompresses digital audio data according to a given audio file format or streaming audio format. ... The 6-pin and 4-pin FireWire Connectors The alternative ethernet-style cabling used by 1394c FireWire is Apple Inc. ... Super I/O is the name given to a class of I/O controller integrated circuits that began to be used on personal computer motherboards in the late 1980s. ...