What are the Different Motherboard Components and Their Functions?

Understanding your motherboard components and their functions is simple... Join us as we explain the different parts of a motherboard with pictures.

At the first glance, the components of a motherboard can appear complicated... even daunting to some. How are we supposed to figure out that jumble of connectors, ports, slots, sockets and heat sinks?

The good news: To find your way around a motherboard, all you'll need to know are the major motherboard parts and their functions.

And what better way is there... than to do it with labelled photos? Let's take a closer look at the different motherboard components below:

Motherboard Components

1. Back Panel Connectors & Ports





Connectors and ports for connecting the computer to external devices such as display ports, audio ports, USB ports, Ethernet ports, PS/2 ports etc. See image below for a close-up view.

For details on the individual back panel ports, click here for our guide to computer cable connections.

Motherboard Back Panel Connectors

2. PCI Slots







3. PCI Express x1 Slots




4. PCI Express x16 Slot



5. Northbridge








6. CPU Socket


7. ATX 12V Power Connector

PCI: Peripheral Component Interconnect

Slot for older expansion cards such as sound cards, network cards, connector cards. See image below for a close-up view.

Have been largely replaced by PCI-Express x1 slots (see motherboard parts #3 below).

Slot for modern expansion cards such as sound cards, network cards (Wi-Fi, Ethernet, Bluetooth), connector cards (USB, FireWire, eSATA) and certain low-end graphics cards. See image below for a close-up view.

Slot for discrete graphic cards and high bandwidth devices such as top-end solid state drives. See image below for a close-up view.

Also known as Memory Controller Hub (MCH).

Chipset that allows the CPU to communicate with the RAM and graphics card.

Beginning from the Sandy Bridge generation of Intel CPUs, motherboards no longer have this component as it has been integrated within the CPU itself.

Insert CPU here. To learn how to install a CPU, click here for our guide to installing a CPU.

Connects to the 4-pin power cable of a power supply unit which supplies power to the CPU.

Motherboard Parts

8. Front Panel USB 2.0 Connectors

9. Front Panel Connectors






10. IDE Connector





11. CMOS Battery





12. Southbridge






13. SATA Connectors



14. Fan Headers



15. RAM Slots


16. ATX Power Connector

Connects to USB 2.0 ports at the front or top of a computer case. See image above for a close-up view.

Connects to the power switch, reset switch, power LED, hard drive LED and front audio ports of a computer case. See image above for a close-up view.

For more details on the individual front panel ports, click here for our guide to installing a motherboard.

Connects to older hard drive disks and optical drives for data transfer. See image above for a close-up view.

Have been replaced over by SATA connectors (see motherboard components #13 below).

Supplies power to store BIOS settings and keep the real-time clock running. See image above for a close-up view.

The CMOS battery found on most motherboards is the CR2032 lithium coin cell.

Also known as the Input/Output Controller Hub (ICH).

Chipset that allows the CPU to communicate with PCI slots, PCI-Express x 1 slots (expansion cards), SATA connectors (hard drives, optical drives), USB ports (USB devices), Ethernet ports and on-board audio.

Connects to modern hard disk drives, solid state drives and optical drives for data transfer. See image above for a close-up view.

Supplies power to the CPU heat sink fan and computer case fans. See image above for a close-up view.


Insert RAM here. To learn how to install RAM, click here for our guide to installing RAM.

Connects to the 24-pin ATX power cable of a power supply unit which supplies power to the motherboard.

Parts of Motherboard

17. mSATA Connector



18. Front Panel USB 3.0 Connector

19. Power & Reset Button



Connects to a mSATA solid state drive. In most cases, this SSD is used as cache to speed up hard disk drives, but it's possible to re-purpose it as a regular hard drive.

Connects to USB 3.0 ports at the front or top of the computer case.

Onboard button to turn on, turn off and reboot the computer.

This motherboard component is more common among high end boards.

RELATED: Best Motherboard CPU Combo 2014

Motherboard Guide