Device Connectors and Cables – CompTIA A+ 220-901 – 1.11

Our computing devices use many different connection types. In this video, you’ll learn about connections and cables that are used inside and outside of the computer case.

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There are many ways to plug-in our different computer components. And in this video, we’ll look at all the different device connectors and cables that you might run into. SATA connectors have a very distinctive shape. You can see the seven-pin data connector and the 15-pin power connector here.

These look to be on the back of a mobile storage device. And you can see the small L-shaped connectors for both the data and the power. That little notch that’s on the data and the power connection means that there’s only one way to put it onto this particular unit. So that it makes it foolproof for connecting our SATA devices.

One good test of your troubleshooting skills will be identifying the different components on a motherboard. And on this motherboard, we’re looking for the SATA interfaces. I can see the normal expansion slots. There’s a slot for a CPU. Here’s our main power. And way in the back, you can see this yellow connector for the SATA interface.

Here’s a closer view of a motherboard where there are four different SATA connectors. You can see the distinctive L-shaped connector for the data. And of course you can only fit one SATA device on each individual interface on the motherboard. The power for the SATA device is going to come from the power supply. So we’ve got a cable coming from the power supply and a cable coming from these data interfaces meeting up at the SATA device.

With SATA, we have both the internal SATA connections and the eSATA, or external SATA connections. And if you put these connectors next to each other, they’re very similar in size. But if you look closely, they do look a little bit different. We can see that the eSATA on the inside is more of a square, whereas with our normal internal SATA, we have more of that L-shaped connector on the inside.

You should be able to look at any computing device and understand what interfaces might be there. I’ve labeled these for our use. You can see there is a DisplayPort connector on this laptop. It also has an eSATA connector. You have two external USB connectors here and a FireWire connector on this as well.

USB connections will be some of the most common ones that you use on your computer. Here are the connectors for USB 1.1 and USB 2.0. The standard-A plug is the one that normally plugs into your computer. And the other interfaces are the ones the plug into the external devices. Standard-B plug is shown here. You’ll usually find the smaller plugs on your mobile devices, such as a mini-B plug or a micro-B plug.

The USB 3.0 standard-A plug is exactly the same form factor as the USB 1.1 and the USB 2.0 standard-A plug. And it’s designed that way for backwards compatibility. There are some additional pins inside of the USB 3.0 plug which make it a bit different internally than the USB 2.0 or 1.1 cables. You can see that the standard-B plug and the micro-B plug on USB 3.0 are very different than previous versions. So you want to make sure that you’re using the right cable for the right USB interface.

Here’s our motherboard, again. And we can pick out the USB connectors. They are on the back of this motherboard. And you can see there are four USB interfaces right here near the bottom. We might even assume from this that these are the USB 1.1 or USB 2.0 connectors because they have the black color with the plastic. If these were 3.0 interface, they would usually be colored blue to designate that higher speed connection.

FireWire or IEEE 1394 has these types of connections. I put these side by side with the USB plug so you can get a feel for exactly how large these connectors are. This is a six-pin Alpha connector. It is a power connector. There’s also a four-pin Alpha connector. It is an unpowered connector. And you can see the faster 800 megabit nine-pin Beta connector here, and it also provides power.

Here’s the back of a driver array. You can see there are many different types of connectors on here. There is USB type-A connectors and a USB 2.0 type-B connector. And here are the three FireWire connectors. There’s the S400, S800, and another S800. The S stands for speed. This is the speed of that interface in megabits per second. This is an Alpha connector, or an S400 connector. And then you can see the 800 megabit connectors, or the Beta connectors next to that.

If you’re working with some older motherboards, you may see a mouse and a keyboard plugged in with these PS/2 connectors. These are six-pin mini-DIN connectors. You can see the six pins inside of these connectors. And they are effectively exactly the same size. This makes it difficult to discern where we’re plugging in the mouse and where we’re plugging in the keyboard.

There is a standard coloring scheme using the PC system design guide where the keyboard is colored purple and the mouse is colored green. We call this the PS/2 connector because it became popular with the IBM PS/2 computer. This was the standard type used for the mouse and the keyboard on that computer. These days, USB is used for our mouse and our keyboard. So you’ll only find these PS/2 connectors on older motherboards.

Here’s the back of an older KVM switch. KVM stands for keyboard, video, mouse. This allows us to connect a single keyboard, video, and mouse to multiple computers, simultaneously. And you can see the mini-DIN PS/2 connectors are down here. There’s the purple keyboard and the green mouse connector that’s used.

It’s very common to find these analog audio ports on your computer. And they often use these three and 1/2 millimeter TRS plugs. The TRS stands for tip, ring, and sleeve, which is referring to the tip, the ring, and the sleeve section of the connector. You’ll often see on the back of a motherboard many TRS interfaces.

And they might have different colors. This coloring scheme is not standardized. So on one motherboard, you might have a left channel that’s colored red. And on another motherboard, you might have a left channel colored black. So you have to be very careful to plug in the right cable to the right connector.

Here’s a good example of some of the TRS connectors on the back of this motherboard. T They’re right next to these USB and an RJ45 connector for the Ethernet. And this is where you would connect that three and 1/2 millimeter TRS jack.