South
bridge is a ball grid array in a core logic chipset on the motherboard.
The South bridge is called ICH(I/O CONTROLLER HUB) on Intel boards but
referred to as South bridge on AMD boards.
The
South bridge chipset handles all computer input/output function such as
serial, audio, USB, system bios, ISA bus, mass storage controllers,
power management.
MASS STORAGE CONTROLLERS:Mass storage controllers such as PATA/SATA which allows for attachment of harddrives.
SPI BUS: This is a serial bus which is used for firmware (bios) storage access.
ISA
BUS:ISA BUS remains an integral part of modern South bridge, although
modern South bridge no longer have provision for ISA BUS. This bus
creates a control path to the super input/output controller(SIO CHIP).
DMA CONTROLLERS: This section of the South bridge provides access to the main memory unit without the assistance of the CPU.
POWER
MANAGEMENT (APM and ACPI):The APM and ACPI provides signalling for the
computer to sleep, shut down, hibernate or power on.
REAL-TIME CLOCK: The real-time clock provides a time account for the system.
INTERRUPT CONTROLLERS:This section provides access route for other devices to access the central processing unit.