The two most important chips on the motherboard, the north bridge is responsible for the data exchange between the CPU and memory, and the graphics card, and the south bridge is responsible for the data exchange between the CPU and the PCI bus and external devices. How to distinguish: In the ATX board type motherboard (that is, the vast majority of motherboards now), the chip near the CPU is the north bridge, the North bridge is the largest chip on the motherboard, often covered with heat sink or fan; The south bridge, on the edge of the PCI slot, is smaller than the north bridge but larger than the other chips. They can't be taken down.