A motherboard chipset is a crucial component of a computer's motherboard that manages data flow between the processor, memory, and other peripherals. It consists of two main parts: the northbridge, which connects the CPU to high-speed devices like RAM and graphics cards, and the southbridge, which handles slower connections such as hard drives and USB ports. The chipset determines the motherboard's capabilities, including supported processors, memory types, and expansion slots. Different chipsets are designed for various purposes, such as gaming or business, influencing overall system performance and compatibility with other components like graphics cards and storage devices.