Northbridge

Also known as the PAC (PCI/AGP Controller) or nb, the Northbridge is an integrated circuit which communicates between the CPU interface, AGP, and memory. The northbridge is directly connected to these components, unlike the southbridge. It acts as a "bridge" between the southbridge chip and the CPU, RAM, and graphics controller. Currently the northbridge consists of a single chip that sits north of the PCI bus. However, early computers may have had three separate chips that made up the northbridge.

The ASUS P5AD2-E motherboard is illustrated below with labels for each component, including the northbridge. The northbridge and southbridge typically have a dedicated heat sink. Furthermore, the northbridge is usually larger than the southbridge, and it is located closer to the CPU and memory.

The northbridge memory controller receives a request from the CPU when it needs data from RAM. RAM. When a request for reading memory over the front-side bus is received, the northbridge replies with how long the processor needs to wait. Newer motherboards have IHA in place of the northbridge and southbridge.

On my motherboard, there is no northbridge.

The northbridge chip is being moved to other CPU components, including the southbridge, as manufacturers look for ways to improve performance and reduce costs. AMD64 AMD and Intel Nehalem processors moved the memory controller from the northbridge to the processor die. AMD's Accelerated Processing Units and Intel's Sandy Bridge processors put all northbridge functions on the CPU.

Also known as the PAC (PCI/AGP Controller) or nb, the Northbridge is an integrated circuit which communicates between the CPU interface, AGP, and memory. The northbridge is directly connected to these components, unlike the southbridge. It acts as a "bridge" between the southbridge chip and the CPU, RAM, and graphics controller. Currently the northbridge consists of a single chip that sits north of the PCI bus. However, early computers may have had three separate chips that made up the northbridge.

The ASUS P5AD2-E motherboard is illustrated below with labels for each component, including the northbridge. The northbridge and southbridge typically have a dedicated heat sink. Furthermore, the northbridge is usually larger than the southbridge, and it is located closer to the CPU and memory.

The northbridge memory controller receives a request from the CPU when it needs data from RAM. RAM. When a request for reading memory over the front-side bus is received, the northbridge replies with how long the processor needs to wait. Newer motherboards have IHA in place of the northbridge and southbridge.

On my motherboard, there is no northbridge.

The northbridge chip is being moved to other CPU components, including the southbridge, as manufacturers look for ways to improve performance and reduce costs. AMD64 AMD and Intel Nehalem processors moved the memory controller from the northbridge to the processor die. AMD's Accelerated Processing Units and Intel's Sandy Bridge processors put all northbridge functions on the CPU.