Video Connections With HDMI
The VGA is the common standard connector found on computer monitors to connect them to the computer. Originating with the 1987 IBM PS/2 model and later on the Dell PIX and its VGA model, the VGA standard has gone on to become quite ubiquitous on PCs, and even some flat panel TVs, projectors and other high resolution television sets. There are also many smaller versions of the standard, called VGA adapters. You can connect a VGA monitor to a regular computer using a standard VGA cable, or connect your VGA monitor to a computer via VGA’s digital output port, called DVI. There are also audio and video connectors referred to as Digital Video Bus or HDMI that are used to connect VGA monitors to televisions and other home entertainment systems. The VGA card is what provides the image to be displayed on the monitor.
A VGA monitor is designed with one or more D-Sub connectors on the back of the screen. The DVI connections are not used with VGA. These early monitors used analog signals sent through VGA cables and provided higher resolutions than the improved DVI signals that are available today. The analog signal was transmitted via vertical and horizontal lines, which only made the colors on the screen uniform. Standard VGA monitors were unable to display resolution beyond 72×32 pixels.
A VGA monitor uses a different connection process than an HDMI or DVI connection, and this difference is the reason that they are not interchanged when connecting a VGA video device to a HDTV. The VGA uses a data stream to communicate with a video game console, providing a pixel-based output of the video. This is different from the digital signal being passed through an HDMI cable, which is actually a compression format. In order to receive a full digital signal, the VGA must compress the analog signal in order to be larger and make it acceptable over a standard connection.
An advantage of using a VGA connection to send the video signal to a computer is that the image quality is higher quality than with any other connection. The VGA uses a compression pattern to reduce the bandwidth used, but this also limits how many colors can be displayed on the monitor. A VGA can support up to 5 colors, whereas an HDMI will provide ten colors. There is no option to change the refresh rate of the video signal, but a VGA can provide a true 24-bit color resolution and greater color accuracy than an HDMI.
To use a VGA to HDMI cable, you need certain devices to make this possible. If your computer does not already have these, you will need to purchase some DVI to HDMI adapters or other converter devices. These devices will convert a DVI source into an HDMI signal. Most computers will have ports for DVI sources, but they may not all be compatible with HDMI. Some manufacturers create adapters that use different connection types, but not all adapters will work with all devices.
Other types of VGA to HDMI connections include displayport and screen port adapters. Displayport adapters allow one VGA to be connected to more than one display port on a computer or television, whereas a screen port will allow one VGA to be connected to a Display Port, which is basically a type of printer port. You can connect a VGA to an HDTV, using a HDMI to DVI or DisplayPort cable, or a VGA to an HDTV, using a HDMI to DVI or DisplayPort cable. This allows you to connect your VGA devices to your television, giving you better picture quality than with any other connection.