Bridges

North Bridge

A north brige is known as memory controller hub in Intel systems. (AMS via six and other usually use North Bridge).

North Bridge contains one of the two chips in the core logic chipset on a pc mother board

North Bridge typically handles communication between the CPU RAM AGP OR PCI and South Bridge.

Some North bridge also contains integrated video controllers which are also known as graphical hub.

Because different processors and RAM needs different kind of signaling, North Bridge will be typically work with only one or two classes of processors and only one type of ram

Ex: North Bridge from NIVDIA NFORCE2 chipset will only work with as socket A processor combined with DDR SDRAM only.

Intel i875 chipset works with Pentium 4 or Celeron processor combined with DDR and SDRAM.

Intel 1915g chipset works with p4 and Celeron but it use DDR or DDR2 ram memory.

The North Bridge and South Bridge chips compromise what is known as a chipset on modern computers.

The chipset is responsible for the communication between the CPU unit and various components of Motherboard.

In many cases North Bridge has its own heat sink for reducing the heat.

It is located very closer to CPU and controller.

Faster components on Motherboard are CPU AGP RAM

If the CPU cache is located on the Motherboard it also falls under the control of North bridge.

These components are all North Bridge connected to North Bridge via paths known as buses.

Computer performance also depends on buses.

SOUTH BRIDGE

South Bridge handles the slower traffic on a compute or the i/o device.

South bridge accesses SATA and IDE (PATA) hard drives and Expansions slots, RAID, USB, FIREWIRE, and DIRECT ACCESS MEMORY (DMA) Controllers.

Also system clock power management interrupt controller and audio codecs all fall under the control of the South Bridge chip.