What Is A Motherboard? - TechTarget

How do motherboards work?

The PCB of a large motherboard can include six to 14 layers of fiberglass, copper connecting traces and copper planes for power and signal isolation. Other components get added to a motherboard through expansion slots. These include one or more CPU sockets; memory slots for dual in-line memory modules (DIMM); Peripheral Component Interconnect (PCI), PCI Express (PCIe) and solid-state drive storage device M.2 slots; as well as power supply connections.

A heatsink and fan manage the heat generated by components such as the CPU. Typically, motherboards offer additional connectivity to peripheral devices through a Southbridge chip such as PCI, Serial Advanced Technology Attachment (SATA), Thunderbolt (hardware interface), USB and other interfaces. A Northbridge chip connects the CPU, memory and storage components.

The CPU is generally connected to double data rate 3 (DDR3), DDR4, DDR5 or onboard low-power double data rate (LPDDRx ) RAM and PCIe. Connections are made through point-to-point interconnects, such as AMD HyperTransport bus architecture, Intel's QuickPath Interconnect (for CPUs) and Ultra Path Interconnect (superseded QuickPath Interconnect). Choosing a motherboard often determines many features a computer will be able to support.

Motherboard designs in desktop computers typically are the ATX motherboard, which is Intel's improved version of IBM's AT design. Other form factor designs include the following:

• Extended ATX.
• Mini-ATX.
• MicroATX.
• BTX.
• MicroBTX.
• Mini-ITX.
• Micro-ITX.
• Nano-ITX.

When determining a motherboard's form factor, check the technical specifications printed on its package, measure the board's dimensions, and examine the number of expansion slots.

Some memory controllers are now built into CPU functionality which eliminates the need for the Northbridge chips that provided memory management. Integrated video has moved from a motherboard slotted peripheral to graphics-enabled CPUs.

AMD's Ryzen has a system-on-a-chip (SoC) design that also makes the Southbridge chipset optional. This CPU integration has cut motherboard manufacturers' costs. They can offer base systems for workstations and entry-level computers and design customized implementations for various processors that enable platform upgrades.

Gaming motherboards are made for high-performance computers; they are more powerful and have more features than motherboards for desktop and laptop computers.