Overview
The Southbridge is the component of the chipset that handles the 'slower' I/O functions of the motherboard. It communicates with the CPU via the Northbridge (or directly in modern systems).
Responsibilities
- USB controllers.
- SATA/storage interfaces.
- Ethernet and audio controllers.
- BIOS/UEFI interface.
- Legacy expansion slots (like PCI).
Modern Equivalent
In modern systems, the Southbridge is often referred to as the PCH (Platform Controller Hub) by Intel or simply the Chipset by AMD.