Our monitors and displays connect to our computers using a number of different methods. In this video, you’ll learn about HDMI, DisplayPort, DVI, VGA, and video over USB-C.
If you’re connecting a computer to a screen, or really, any type of consumer electronics to a video display device, then you’re probably using HDMI. That stands for High Definition Multimedia Interface. This sends both audio and video through the same digital connection, and it has about a 20-meter maximum range before you start to lose too much signal and start seeing blockiness on the screen.
This is one of the most common connector types that you’ll find on today’s monitors and televisions. It’s a 19-pin connector, and it’s referred to in HDMI as a Type A connector.
Here’s a video adapter that has a number of different outputs. It has DVI and DisplayPort, but it also has an HDMI connection right here at the bottom. You can see that it’s almost in the shape of a rectangle, but the bottom corners are indented in just a bit, which means that an HDMI cable would be the only thing that would fit into that interface.
On that picture of the display adapter, we saw that one of those interfaces was a DisplayPort interface. Displayport is a video format that is also able to send audio and video over the same connection, and it was one of the first display-type connections that send it in a packetized form, very similar to how you might send information over an ethernet network.
This also has some compatibility with both HDMI and DVI. You can use a passive adapter to convert between DisplayPort to HDMI or DisplayPort to DVI. On some devices, you may find that the DisplayPort interface is the smaller style, known as the mini DisplayPort, but on desktop computers and video interface cards, you’ll probably find the full-sized DisplayPort connector.
Notice that the DisplayPort connector has small little locks along the top of the connector, and when you plug it into the interface, it tends to lock in place. This means that connector will not accidentally pull out of that connector, and usually there’s a button along the top or the sides of the connector that allow you to unlock the connection so you can pull it out of the interface.
If you are trying to disconnect a cable connection from a computer and you notice that it’s not coming out of that connection, then it probably is a DisplayPort interface and you’ll need to press down on that button before removing it from the computer.
Here’s another video card with many different types of video outputs– not just DVI and HDMI, but a number of different DisplayPort connections. You’ll notice that DisplayPort and HDMI are similar to each other, at least in size, but they are very different in their form factor. You’ll notice the DisplayPort is a bit of a rectangle with one of the corners that’s a little bit slanted. That means that you can’t accidentally plug in HDMI to DisplayPort, or vice versa.
If you’re working with some older systems, you may run into a DVI interface. That stands for Digital Visual Interface. One of the challenges with DVI is that it’s a single connector type with multiple types of connections. So you can see, there’s a DVI-A, DVI-D single link, DVI-D dual link, and so on.
As the name implies, a single-link and a dual-link video connection are able to send different amounts of traffic, effectively doubling on the dual-link connection. A single link can transmit information at approximately 3.7 gigabits per second, which is able to support a traditional HD connection, which is 1920-by-1200 in resolution.
We saw with HDMI and DisplayPort that we were able to send both audio and video through the same connection. If you’re plugging into a DVI connection, you are only sending video signals through that connector.
You might also run into some other variations of DVI, such as the DVI-A that’s able to send analog signals. This is a standard connector that is able to coexist or be backwards-compatible with VGA. We’ll look at VGA connectors in just a moment.
DVI-D connectors are sending digital information. And if you run into a DVI-I connection– that is, a DVI integrated connection, it can send both digital and analog signals in the same connector.
If you are working with DVI, make sure you look at the connector that’s on your computer and the connector that you’re using for your cable to make sure you’re using the proper connection for both of those devices. And depending on the video card that you’re using, you might have an option as to which DVI connector you might use, so it’s important to know that there are differences, and you’ll need to make the right decision over which interface would be the best one to use for your purposes.
Legacy equipment tends to use a video standard known as VGA. This is the Video Graphics Array standard. VGA uses this standard connector we refer to as a DB-15 connector. There are 15 pins inside of the connector, and the connector itself is shaped like the letter D.
The size of this connector is an E shape. Technically speaking, this is called a DE-15, but you’ll also see it commonly written as DB-15. You’ll also notice that VGA connectors tend to have a very standard blue color associated with them. That’s because there are a series of standardized colors that were rolled out as part of a PC System Design Guide.
VGA, very similar to DVI, only sends video signals through this link. We don’t send any audio over these VGA connectors. And because this is an analog signal, we tend to start seeing a degrading of signal once we get past five or meters of total cable length.
Here’s the back of a motherboard that supports a number of different video types. There is HDMI plugged into a connector. We can see there’s VGA on this motherboard. This motherboard also supports a DVI connection.
Although we tend to see a number of different video standards, fortunately, the connector types are very different between all three, so it should be very easy to differentiate between VGA, DVI, and HDMI.
These days, we’re also sending a lot of video signals over a USB-C connector. USB-C is a connector type, and there could be a number of different signals going across that particular cable.
For example, USB could be sending power or serial data over that connection, but we could also put Thunderbolt data, DisplayPort, HDMI, and a type of connections for mobile devices called a Mobile High-definition Link, or MHL. This means some devices are able to send many different types of signals over that same USB connection, and all we need is to provide the right cable and the right connection.