While shorter VGA cables are less likely to introduce significant signal degradation, good-quality cable should not suffer from signal crosstalk (whereby signals in one wire induce unwanted currents in adjacent wires) even at greater lengths. There are no standards defining the quality required for each resolution, but higher-quality cables typically contain coaxial wiring and insulation that make them thicker.
The same VGA cable can be used with a variety of supported VGA resolutions, ranging from 320×400px or 320×480px (12.6 MHz of signal bandwidth) to 1280×1024px ( SXGA) (160 MHz) and up to 2048×1536px ( QXGA) (388 MHz). ( April 2021) ( Learn how and when to remove this template message) Unsourced material may be challenged and removed. Please help improve this section by adding citations to reliable sources. The IBM PS/55 Display Adapter redefined pin 9 as "+12V", which signals the monitor to turn on when the system unit is powered on.
Devices that comply with the DDC host system standard provide 5 V ± 5%, from 50 mA to 1 A. With the implementation of the VESA DDC specification, several of the monitor ID pins were reassigned for use by DDC signaling, and the key pin was replaced with a +5 V DC output per the DDC spec. Some pins on the connector were also different: pin 9 was keyed by plugging the female connector hole, and four pins carried the monitor ID. In the original IBM VGA implementation, refresh rates were limited to two vertical (60 and 70 Hz) and three horizontal frequencies, all of which were communicated to the monitor using combinations of different polarity H and V sync signals. The VESA DDC specification does, however, include a standard for hot-swapping. The VGA interface includes no affordances for hot swapping, the ability to connect or disconnect the output device during operation, although in practice this can be done and usually does not cause damage to the hardware or other problems. In both its modern and original variants, VGA utilizes multiple scan rates, so attached devices such as monitors are multisync by necessity. Modern connectors also include VESA DDC pins, for identifying attached display devices. DE-15 is the accurate nomenclature under the D-sub specifications: an "E" size D-sub connector, with 15 pins in three rows.Īll VGA connectors carry analog RGBHV (red, green, blue, horizontal sync, vertical sync) video signals. The VGA connector is a three-row, 15-pin D-subminiature connector referred to variously as DE-15, HD-15 or erroneously DB-15(HD). ĭevices continue to be manufactured with VGA connectors, although newer digital interfaces such as DVI, HDMI and DisplayPort are increasingly displacing VGA, and many modern computers and other devices do not include it. Other connectors have been used to carry VGA-compatible signals, such as mini-VGA or BNC, but " VGA connector" typically refers to this design. Originating with the 1987 IBM PS/2 and its VGA graphics system, the 15-pin connector went on to become ubiquitous on PCs, as well as many monitors, projectors and high-definition television sets. The Video Graphics Array ( VGA) connector is a standard connector used for computer video output. In the male connector, this pin numbering corresponds with the cable's wire-and-solder side.
The image and table detail the 15-pin VESA DDC2/E-DDC connector the diagram's pin numbering is that of a female connector functioning as the graphics adapter output. I☬ clock since DDC2, formerly monitor id. Reserved since E-DDC, formerly monitor id. +5 V DC (powers EDID EEPROM chip on some monitors), formerly key
JACK SPLITTER PLUS
RGB video signal plus option H and V sync A female DE-15 output in a laptop computer
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