Motherboard Connectors – CompTIA A+ 220-1001 – 3.5

| February 10, 2019


There are numerous connectors on a motherboard that can be used for CPUs, storage devices, and other peripherals. In this video, you’ll learn about CPU sockets, storage interfaces, and integrating your computer case with your motherboard.

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One of the most significant connectors on any motherboard is the CPU, or central processing unit. The CPU is one that is matched to the motherboard. The motherboard has been specifically engineered for certain types of CPUs. In some cases, only a single CPU is matched with a particular motherboard.

And as you can see on this motherboard, the CPU is the largest connector. And it’s right in the middle of the motherboard. It’s in the middle because we will have the memory slots that will be communicating to the CPU. Expansion cards will be communicating to the CPU, and other components on this motherboard will be sending information and receiving information from this central processing unit.

Because the motherboard and the CPU are so closely engineered together, this is not a component that you would generally upgrade later. There are some motherboards that do have some options for different CPU models. But those options are usually limited, and it’s not the easiest upgrade to remove an existing CPU and replace it with a new one.

One of the socket types that you’ll see on a motherboard is a zero insertion force, or a ZIF socket. One of the fundamental characteristics of a ZIF socket is that it is full of little holes. These holes will be matched with pins that are in the CPU.

And the ZIF socket itself has an arm that you would lift up. You would simply place the CPU into this socket, and then you replace the arm. It’s a very simple process that allows you to install that CPU very securely, but you don’t have to push down or apply any pressure to make sure that that connection is made.

All of those holes that are in the CPU socket are matching with pins that are on the CPU itself. This type of package for a CPU is called a pin grid array, or PGA. So a PGA is going to plug into a ZIF socket.

The top of the CPU is relatively flat. All of the pins are on the bottom of the CPU. And if you look closely, there are many, many pins that are plugging into that zero insertion force socket.

Another type of socket you’ll see in a motherboard is the reverse of the ZIF and the PGA. It’s the land grid array socket, or the LGA. The pins for an LGA are on the motherboard, and the CPU itself is completely flat on the bottom.

This means that you don’t have to worry about bending any of those pins on the CPU as you’re moving the CPU around and getting it ready to install. Of course, you do have to be very careful that you don’t drop anything on the motherboard because you don’t want to bend any pins on that LGA socket. And as you can see, there are a lot of pins on that LGA socket. They go all the way around the edge of that CPU.

And of course, the bottom of the CPU, then, is going to be completely flat. You can see the copper connectors that correlate to each one of those pins on the motherboard. If we look closely, you can see what all of those connectors look like. The center of this CPU has some capacitors, and then the connectors that plug into the LGA socket are around the outside.

Another common connector type on our motherboards is for our storage devices. It’s common to see SATA connectors on the bottom. This particular motherboard has four different SATA connectors, labeled 0 through 3. And we can, of course, plug four individual storage devices into those individual SATA interfaces on the motherboard.

Some motherboards will support different kinds of interfaces for storage devices. This motherboard supports four different SATA connectors, but it also has an IDE connector, or what we call a PATA connector. That means that we can connect both SATA devices and the legacy PATA devices all on the same motherboard.

Here’s another picture of an IDE or a PATA interface on a motherboard. You’ll also notice on this motherboard just underneath the IDE connector are all of these smaller connectors. They look like jumpers, but they’re really designed to plug in connections from your computer case. And they’re labeled power, hard disk drive, network interface card one, network interface card two, and so on. Those small pin connectors are used to connect these interfaces that are on the front or the top of a computer case onto the motherboard.

If we look closely inside of a computer case that doesn’t have anything installed in it, the case itself comes with interfaces on the top for USB and audio. And all of those wires are ready to be installed and connected to those smaller interfaces on the motherboard. Most computer cases will label the end of those wires. So you can see the wires themselves might say reset switch, hard drive LED, power LED, and any other interfaces that happen to be connected on that computer case.

Once we know what those wires are for, we can find the spot on the motherboard that would correlate back to that particular wire. So we’d find the wire that says it’s for the power button. We would find the connectors for the power button on the motherboard, and we’d connect those wires directly to the motherboard interface.

If you look at the back panel of a motherboard, you’ll probably see USB connectors that are directly connected to the motherboard. These might be used for keyboard, mouse, and printer type connections or anything else that needs USB. But there’s also USB connectors that are on the computer case, and we need some way to connect those USB interfaces to the motherboard as well.

Here’s an example of where you would connect the USB interfaces on the case to the USB interfaces on the motherboard. This is an Asus Micro-ATX motherboard, and you can see the spot for the CPU and the memory and the expansion slot. But down here at the bottom are two interfaces for USB. And those two interfaces are for USB 2.0 connectors that would be on the case and USB 3.0 connectors that might be on the case.

If we go back and look at that picture of our case with nothing installed, there are USB connectors on the top of this case. And if you look closely at the bottom, you will see there is a connector for USB 3.0 and USB 2.0 connectors.

Here’s what everything looks like once you’ve filled in the computer case. You’ve got your power supply, your motherboard. The CPU is installed with the memory.

You’ve got some expansion slots. And of course, this case has interfaces on the front for USB, for audio. And of course, there’s a power button and a reset button on the front.

Those wires are connecting directly from the front of that case to the interfaces on the motherboard. So now we know when we push the power button or use the USB interfaces that we’ll have a connection directly to this motherboard.

Category: CompTIA A+ 220-1001

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