There are many different ways to connect your computer to your display device. In this video, you’ll learn about DVI, DisplayPort, RCA, VGA, HDMI, and more.
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-One very common display interface type is the DVI interface. The stands for Digital Visual Interface. There’s two different versions of this. A single link and a dual link.
The single link is one that can run up to 3.7 gigabits per second. So you can have full HD at 60 frames per second. If you have a higher resolution, or you want a higher frame rate, you may want to run dueling DVI. This runs at 7.4 gigabits per second, and allows you to have HDTV signals at 85 frames per second.
As you can see here on the left, there are many different flavors of DVI interface. Some are DVI-A, others are DVI-D, and others are DVI-I.
The DVI-A stands for analog signals. We don’t generally see DVI being used for analog signals, but the specification does have an interface and a type that does support sending analog information over a DVI link.
DVI-D then is the DVI for digital signals. And you can see the two DVI-D connectors are here for the single link, and the dual link. You’ll see there are a number of pin differences between those two interface types.
And the last type of DVI interface is DVI-I. The I stands for Integrated, so it’s combining digital and analog signals in the same connector. You can see both the single link and the dual link connector here at the bottom for the DVI-I.
Here’s a DVI-D single link connector. You can see the pins out on the end of that. Right next to it is an HDMI I connection and a VGA connection. So you can compare the sizes. You can see the DVI is a little bit larger in its connector type in those other two specifications.
Another popular video interface type is the DisplayPort. DisplayPort is a VESA standard. VESA is the Video Electronics Standards Association, and its a royalty-free standard, which means that many factors can add DisplayPort interfaces to their devices without having to pay any extra licensing fees.
DisplayPort works very much like the ethernet networks we use for information is packetized and sent in a digital form over these links. It’s also very similar to how PCI express works. We’ve taken that same idea and applied it to the DisplayPort connectivity.
DisplayPort is also compatible with HDMI DVI. There’s a passive connector you can use if you’re using the same digital type of communication over these DisplayPort connections.
Here’s a DisplayPort connector on a laptop. You can see it has a very different style than an eSATA, or a USB, or even the very small FireWire 400 connector.
Another connector that’s been around for a very long time is the RCA connector. This was designed by the RCA Corporation in the 1940s. You will also hear this referred to as a phono connector. And you could of course, see RCA used not only for video, but often to connect audio components as well.
If you’re using some older monitors, you may be connecting them with an RCA connector to use composite video. This uses a single RCA connector for the video, sending a single channel of analog video. You’ll often see this yellow RCA connector combined with a white and a red RCA connector. The yellow is sending the video and the red and the white person in the left and right audio channels.
For sending high definition signals over RCA, we use component video. This consists of three separate RCA connectors. One is used for Y, is used for PBb and one is used for Pr. Those abbreviations stand for the Luminance and sync, the Blue and the Red signals.
Here’s a device that supports sending that composite video signal over an RCA cable. You can see the yellow RCA interface on this device. This device also supports sending audio over these RCA connectors. You can see the right and the left channels being represented by the red RCA connector and the white RCA connector.
Here’s a device that supports many kinds of connectors. For the video, it supports both composite, and component, along with HDMI, and other interfaces for external connectivity. If we look closely at these connectors, you can see Y, the Pb, and the Pr used for component video.
And here at the top we have RCA connectors for composite video. There’s a Video In and a Video Out. You can also see the red and white RCA connectors for Audio In and Audio Out. And this device also supports digital audio over this orange RCA connector.
Since the early days of personal computers, we’ve sent analog video over these VGA connectors. That stands for Video Graphics Array. You may see these connectors referred to as a DB-15 connector. The DB stands for d-subminiature size B. You can see that the connector itself does look like the letter D. And the 15 stands for the 15 pins that are inside of the connector.
Interestingly enough, this connector size for the D shell is actually a size E. So technically, this would be a DE-15 connector, but in the industry, we seem to call this the DB-15. And you’ll see that written almost everywhere. You might also see this connector called the HD-15 or HD15, without the dash in the middle. It’s all exactly the same connector for VGA.
Both the cable and the interface on your computer will probably be colored blue. That’s a standard from the PC system design guide. And the VGA connector is designed to carry analog signals only. You won’t see any digital video signals being sent over VGA connection.
Here’s a motherboard that supports a number of different video types. You can see the DB-15 here, being used for VGA. We could also connect to this motherboard via DVI. You can see the DVI connection just underneath. And here’s an HDM I connection. If you wanted to connect to a standard HDMI monitor.
HDMI stands for High-Definition Multimedia Interface. And over this single cable, we can see in both video and audio signals simultaneously. This is a fully digital connection. There is no option to send any analog signal through HDMI. You will commonly see HDM I using a proprietary 19 pin connector. We also call this the Type A connector. You might also see on smaller devices, like cameras or mobile devices, a miniHDMI. this is technically Type C connector and it’s really designed to fit into these smaller spaces.
If we look at the back of a video card, we should now be able to recognize what some of these interfaces are. On the left side we have a DisplayPort. Next to that is an HDMI port. You can see the size of these two is very similar, but you can see that they are shaped very differently. You cannot plug a DisplayPort cable into HDMI or vice versa.
And on the right side we have two different DVI– a DVI-D and a DVI-I. The DVI-I has a cover over, but you can easily see all the different pinouts that are on a DVI-D connection.
You’ll often see BNC connectors used for video and sometimes networking connections. BNC stands for Bayonet Neill-Concelman. The bayonet is the locking mechanism at the end of the cable. And the Neill-Concelman stands for Paul Neill and Carl Concelman, who designed the connector.
We often see these BNC cables being used on higher end video. Especially if we’re concerned about these coming out of an interface accidentally. By connecting it in and twisting it, we’re able to lock the connector. And it’s not very easy to accidentally disconnect or shake that connector out in any way.
For video, we often see the BNC connectors being used for component video. Where you have the Y, the Pb and the Pr connections. Those are the Luminance and sync, the Blue and the Red connectors.
Here’s a better look at the locking mechanism. You can see the bayonet connector fits into these tiny little tabs on the side, and twists into place. And once they’re in place, you can’t pull them out unless you physically untwist that particular connector.
You might also see video being sent over a Mini-DIN-4 connector. This is the Mini-DIN connector. And you can see the four pins that are on the inside. The type of video being sent over these Mini-DIN for connectors is S video. That stands for separate video.
This is a 2-channel analog signal that’s being sent over this Mini-DIN-4. One of the channels is intensity and the other channel is color.
You might also see variance to the Mini-DIN-4, such as the Mini-DIN-7 and Mini-DIN-9, where it’s changing the number of pins that are used inside of the cable.
Here’s a close up of some of these video connectors. And here’s the video S-Video Mini-DIN-4. For you can see the four pins being used on this S-Video connection. We’ve got a composite video connection, with the single yellow. And here’s the Y, the Pb, and the Pr used for component video.