The chipset is a group of chips that facilitate communication between the processor, memory components, and peripheral devices. The chipset controls the bus speed and also power management features. Chipsets are usually attached to the motherboard and are non-upgradeable. Most modern chipsets consist of the following: The northbridge chip provides control for main and cache memory, the front side bus, and the AGP and PCIe graphics. The northbridge is closest to the CPU. The northbridge dictates the CPU and memory type supported by the motherboard. On some motherboards, the northbridge chip includes an integrated graphic processor. The northbridge often has a heat sink and sometimes a fan, especially if it includes built-in video.The southbridge chip provides the real time clock, controls power management, and provides the controllers for the PCI bus and USB devices. There are two other important chipsets on a motherboard: the keyboard controller and the I/O controller.Recent developments for the chipset include:Combining north- and southbridge functions into a single chipset. Moving the memory controller from the northbridge to the CPU itself to improve memory access by the CPU.