In computing, a northbridge (also host bridge, or memory controller hub) is a microchip that comprises the core logic chipset architecture on motherboards to handle high-performance tasks, especially for older personal computers. It is connected directly to a CPU via the front-side bus (FSB), and is usually used in conjunction with a slower southbridge to manage communication between the CPU and other parts of the motherboard.
Historically, separation of functions between CPU, northbridge, and southbridge chips was necessary due to the difficulty of integrating all components onto a single chip die. However, as CPU speeds increased over time, a bottleneck emerged due to limitations caused by data transmission between the CPU and its support chipset. The trend for integrated northbridges began near the end of the 2000s βfor example, the Nvidia GeForce 320M GPU in the 2010 MacBook Air was a northbridge/southbridge/GPU combo chip.
