Motherboard Jumpers and Connectors – CompTIA A+ 220-801: 1.2

There are many jumpers and connectors on the PC motherboard, and it’s useful to know where your case wires connect to your computer. In this video, you’ll learn about these connectors and how to properly connect your cables and wires.

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If you were to look at your motherboard, you would find a lot of different connections on it. There are a lot of different jumpers on it. Some are very obvious, like these big connectors for a hard drive. But you have these much smaller connectors on here as well. And if you notice on the motherboard itself, there is text right next to these little connections that give you an idea of what these are associated with.

If you were to look at the documentation of your motherboard, you would see that these two connectors are for a power LED light that would be on the case, so that you could see what the status was of the power just by looking at the outside case of your computer. Here’s another one for HDD. That stands for your “hard drive status lights.” A NIC1 and a NIC2 probably refers to the status of your network interface card. And here’s one for OH. That stands, in my particular case on this motherboard, for overheating. If your motherboard gets too hot, a light will come on on your computer case so that you can visually see there’s some type of problem happening with your computer.

If we were to look at our computer case, it has a lot of wires coming off of it that are connected to those lights. And the wires generally are labeled on the end so you know where to plug them in. Here’s a few wires. This one says, reset switch. So I would plug this into the connection that I would use to reset the motherboard. There’s the HDD LED. There’s the light that I would plug into that hard drive connection we were looking at. There’s a power LED.

So I can plug this into the place that signifies that there’s power going to the motherboard. And once I plug them all in, they’ll look something like this. I’ve now connected to all of those different connections right there on the motherboard. And they’re all now trailing back to the case itself, so that I can now put the motherboard inside of the case, put the case on the top of it, and have all of those status lights on the front.

The connections that you’ll need to plug in are probably located in many places on the motherboard. They’re probably not going to all be in one place. So you’ll want to look at the documentation of your motherboard to find out exactly what you’ll be plugging in and how you’ll be plugging into those connections. And if you plug them in the wrong way, or you miss a pin when you’re plugging it in, you’ll notice that you’re not getting the light, or you’re not getting the noises you might think you’d be getting through your speaker or through the other devices that you’re plugging in.

Back on the computer case, you’ll have, of course, connections– like a power connection, and a reset connection. And these particular buttons, on these case, have a light built into them that the motherboard will then power and send that information. So you can see at a glance, is it powered on? You also have these connectors for USB ports and other speaker connections. Those wires also will plug into corresponding connections back on the motherboard.

I have another video that’s just about power supplies. But that’s an important connection to your motherboard. There will be a 20 or a 24 pin connection that you’ll be plugging into the motherboard itself that’s coming right from the power supply. It’s one big connection, as you can see here. It’s very obvious to see. And if you look at your motherboard, and you look around at where the different connections are, it’s pretty obvious– in this case, it’s over on the right-hand side– where you might plug-in the power connection. It’s one of the most obvious ones you’ll find on your motherboard.

So there’s all kinds of different connections. Some of them are very small fan connections. Some of them are connections to go back to your case. And some of them are these very large power connections that you’ll find.

There are other connections on your motherboard that are not designed to plug into a floppy drive, a hard drive, or even connections from your motherboard case. These are jumpers. Those are simply pins that you’ll find on the motherboard. Sometimes it’s only a pair of pins. Sometimes it’s more of those. And you’ll have to look at the documentation of your motherboard to determine where the jumpers are and what they mean.

On my motherboard, I have a jumper 13 right here. That’s simply two pins. Now these pins are not shorted. We’ve not connected them together. So there are two statuses for whatever this jumper 13 is signifying. If it is un-jumpered, that has, in this case, a certain speed for my PCI bus, if I jumper them together, I’m lowering the speed. So just by adding a jumper between those two pins, I can change the way my motherboard works.

If you look at the jumper– and it has one of those jumpers that is just halfway on. And the other side isn’t plugged into anything. That is the same as if there isn’t a jumper there at all. It’s simply sitting on that pin, so that later on, you’ll have access to the jumper. You don’t have to find one, rummaging through drawers, or borrowing it from another device. You can simply lift that jumper off and set it right down on top of both of those pins. And now you have shorted those pins together with that jumper.

So before, when I had it un-jumpered, that connection meant that my PCI bus ran at a certain speed. When I jumper them together, it changes the speed of the PCI bus. And you might need to do that depending on what you’d like to plug in to certain connections. You might have other jumpers on your motherboard that might enable or disable sounds.

There’s other jumpers that might enable or disable the clearing of the BIOS configuration. There’s generally a number of different jumpers on your motherboard. So make sure you look at your documentation to determine where those jumpers might be, and what you can modify or change by setting different configurations of those jumpers.