Talk:VGA connector/Archive 1

Archive 1

Terminology help needed

At one point the article says that "one pin was keyed" and that now the "key pin" has been replaced by the +5V power pin. I suspect that most readers don't know what that means. I don't or else I would have added an explanation myself. Mark Foskey (talk) 00:22, 21 September 2012 (UTC)

I've put in an explanation, tell me if it's clear enough. This must have been a rare feature, perhaps only on real IBM-made VGA boards, though I'll have to look to see if pin 9 is missing from current video cables around the house and office. --Wtshymanski (talk) 02:22, 21 September 2012 (UTC)

Adapters section

Is flat out wrong. You can not go from HDMI to VGA with a simple adapter except for a few very select cases. The problem is the HDMI connector (as well as DVI-D) does not carry the analog signal needed by or produced from a VGA connector. There are a couple of cables listed on Amazon (a poor source of information) that make it look like this is possible, but if you read the details it says that you must be using a VGA connector that is capable of carrying a digital signal. At this point the connector is NOT a "VGA" connector, it's a repurposed DE-15 connector. — Preceding unsigned comment added by DracoDan82 (talk • contribs) 16:58, 28 September 2011 (UTC)

Solid references for SCART and RGB-sync-on-green conversion?

I added caption for that with some hook for legibility, but it feels still a little thin for encyclopedia. Has any English-language author covered these bits? — Preceding unsigned comment added by 194.100.83.191 (talk) 20:31, 7 December 2011 (UTC)

Cable Info

How long can a VGA cable be? AndrewRH 19:31, 3 May 2007 (UTC)

As long as a piece of string ;) . Depends on the signal - according to http://www.scala.com/hardware/dvi-vga-cable.html - 10 meters for 1024 x 768 or better, if you using 640 x 480 - probably as much as 100 meters. Megapixie 03:13, 4 May 2007 (UTC)

The characteristics of the particular devices at both ends of the cable are likely to have some effect on the maximum usable length, as will the thickness of the wire and possibly how the ground conductors in the cable are configured, in addition to the resolution being a factor. Furthermore, there's going to be a range of the cable working well, then working poorly, then not working as you extend it. JNW2 (talk) 08:13, 1 January 2008 (UTC)

For long runs you need reasonable quality 75 ohm coax to avoid/reduce reflection issues especially at higher resoloutions/refresh rates. For really long runs it may be better to use short breakout cables and then seperate runs of thick coax. Also in my experiance DDC becomes unreliable on long cable runs which can make setup a little more interesting ;) Plugwash (talk) 00:58, 28 November 2009 (UTC)

Signal Specification

Does anybody know the signal specification? It would be great if we could add a section like the one in Enhanced Graphics Adapter. — Mobius 22:19, 2 June 2006 (UTC)

There is no signal specification because unlike the EGA, the VGA connector is used by many different graphics cards besides the original VGA. Refer to the sentence in the VGA article itself:

It may also refer to the 15-pin D-subminiature VGA connector which is still widely used to carry analog video signals of all resolutions. (emphasis added by me)

131.107.0.103 21:30, 31 July 2006 (UTC)

Where might I find more information on the various types of signals used? 209.42.59.161 15:37, 1 November 2006 (UTC)

if pin 11 is snapped off the plug that goes from the monitor to the computer, is there any reason why it shouldnt work??? ive tried to read info on the pin config but i dont understand. some say GND, some say ID_1... it was working for ages without it, but suddenly everything looks purple... —Preceding unsigned comment added by 210.87.18.76 (talk • contribs)

Could be a problem with the display or the graphics card - is it a CRT ? Wouldn't be unheard of for the green gun to go bad - do the on screen displays look purple too ? or do they comeout okay Megapixie 06:53, 30 October 2006 (UTC)

Is VGA Hot Swap-able?

Is VGA -- officially, in practice without risk, in practice with risk -- hot swap-able? —Preceding unsigned comment added by 75.6.238.37 (talk • contribs)

I don't know the official answer. I do know that the DDC protocol supports it (the monitor grounds a pin so the card knows if it is present and will reinitialize) but electrically I am not sure if surge suppression is required. I do know that the card I worked on showed suppression diodes external to the VGA chip on the chip's datasheet so it is definitely recommended. And I know I've personally yanked out the cable at least a few hundred times in my lifetime. :) — RevRagnarok ^{Talk Contrib} 14:52, 4 November 2006 (UTC)

I would say that in general it is not designed to be a hot-pluggable interface. The screws aside the cable connector speak the same message. Probably with most today's chips the action is taken into account though. I have an experience of a very old graphics card that outputted a B/W image if the (color) monitor was not connected at boot. — 193.64.22.88 (talk) 11:18, 5 December 2011 (UTC)

VGA is much like other conventional PC interfaces in this regard, there is nothing to actively prevent hot-swapping but there is also nothing to ensure that grounds make first and break last so hotplugging may introduce surges in signal lines which may or may not be adequately protected against.

Further complicating matters is that some modern hardware tries to detect whether a monitor is connected and behaves differently depending on what it detects. Again that hardware may or may not continuously monitor for changes.

Connecting Computer to LCD TV

Both have female connectors. To make a lead is it a simple case of getting two male connectors and matching up the pins(name to name), are all fifteen required ? -Teeteetee 20:18, 17 March 2007 (UTC)

Yes VGA cables are pin to pin wired. At an absolute minimum you need the red, green, blue, hsync, vsync and thier associated grounds. If you want the computer to be able to read the screens characteristics with DDC then you will need the DDC pins as well. I doubt the 5V DC pin is used by most stuff given that it wasn't present on older equipment so you can probablly leave that out. Unfortunately obtaining suitable cable seems very difficult the video signals are well into the megahertz so for decent performance you need appropriate 75 ohm coax but if you want DDC you need individual wires for that as well, such cable is used in ready made monitor cables but i've never seen it for sale seperately. You can buy cable with 5x coax which is usable if you don't care about DDC but even that isn't cheap. The bottom line is you are probablly better off buying readymade cables. Plugwash (talk) 15:49, 21 November 2009 (UTC)

VGA-9 to VGA DB15

Can any one tell me if is it possible to adapt a modern monitor (VGA DB15 conector) to operate from an older computer using a VGA-9 connector, older computer is controler for CNC machine. OEM no longer in business updating computer not an option.--24.36.23.59 05:49, 27 April 2007 (UTC)

Are you sure it's even VGA? I thought 9 pin was only CGA or EGA. — RevRagnarok ^{Talk Contrib} 10:47, 27 April 2007 (UTC)

It may not be either, as 9-pin connectors were used for some of the old Atari-era multisync monitors (TV resolution); it may be that hooking it up to a SCART socket would work (with an appropriate TV set, obviously). If that's the case you'd need an upscan converter to run it with a standard VGA monitor (a device that converts TV-standard signals into VGA-compatible ones); having a quick Google for that will find you plenty of options. HTH. Stonejag 15:20, 3 May 2007 (UTC)

The original monitor on this system was from a Commador? 64 with an 8pin DIN connector, the replacement is an old Tandy (RadioShack) multisync monitor, 9pin DBI. I will try the upscan converter, thanks for the info, David

-- Yes there are 9-pin VGA connectors. One example is the Compaq Deskpro 386 from the early 1990's. A socket on the computer side is keyed with a hole filled in (and a pin missing on the monitor plug) so that normal RS-232 serial connectors aren't accidentally plugged into the computer. —Preceding unsigned comment added by 216.255.63.114 (talk) 23:57, 29 December 2010 (UTC)

Naming Semantics

I added a to the section which mentions that the connector is "is almost universally called 'HD-15'" as this is an obvious statement of opinion, and my vga extension cable packaging begs to differ... I've "almost universally" (what does that even mean?) heard it referred to as a DB-15 connector. 24.68.135.133 03:47, 30 June 2007 (UTC)

how to connect VGA out put to normal TV as audio video in put?

can any body tell me how to connect VGA out put to normal TV as audio video in put? —Preceding unsigned comment added by 121.247.120.171 (talk) 09:59, 6 September 2007 (UTC)

please tell me if you got any solution....i have IBM lenovo t60p —Preceding unsigned comment added by 122.169.131.81 (talk) 09:47, 7 October 2007 (UTC)

You'll need to buy a converter. -- Beland (talk) 22:22, 18 December 2007 (UTC)

Pin 9

I have seem some cables advertised as having pin 9 removed "for universal VGA compatibility". Are different pin configurations necessary for any of the VGA-related standards? -- Beland (talk) 22:29, 18 December 2007 (UTC)

Some VGA sockets have the pin 9 hole blanked off, so a plug with all 15 pins won't go into it.

I just bought a VGA cable that has pin 9 missing on both ends, and when I plug it into my LCD television (which has an RGB input) from my laptop, the image appears ghosted slightly, which is really noticeable on the Desktop but not so much with fullscreen games. Is that due to the pin missing? -- SJ2571 (talk) 23:15, 11 November 2008 (UTC)

Cheap unshielded cable is probably the issue. The pin makes no difference. Megapixie (talk) 05:51, 12 November 2008 (UTC)

Cheap cable may be the issue but i've seen this with fairly expensive cables too and monitors seem fine with cheap thin cables. I get the impression that real issue is crappy VGA input circuits in HDTVs. Plugwash (talk) 00:49, 6 December 2009 (UTC)

How-to sections

"Disabling DDC" and "KVM switch problems" are "how-to" sections which are discouraged by Wikipedia; they should either be shortened substantially or removed altogether, as with a similiar "Disabling DDC/CI" section has been removed from Display Data Channel. --82.179.218.11 (talk) 11:28, 24 June 2009 (UTC)

analogic numeric

Does this terme is apply only on the content and not the container ( cable connector). All signal is analogic ? thak's for make this more clear !! 90.7.152.159 (talk) 20:44, 9 August 2009 (UTC)

The Pin 12 problem

To solve this problem you need to remove pin 12 from one end of the VGA cable between KVM switch and VGA monitor.

I don't think that we have to disconnect pin 12 on open source based systems. Can't we just modify the driver so that the system no longer utilizes the DDC information? —Preceding unsigned comment added by Markhobley (talk • contribs) 06:31, 12 August 2009 (UTC)

digital

recently an anon added the following assertion which I have removed.

"However, many modern graphics cards will detect the presence of a DVI or HDMI adapter connected to the HD-15 port and will then send digital data through the port."

I've never heard of this, I don't think i've ever seen a VGA to HDMI adaptor and afaict all the VGA to DVI adaptors i've seen just connect the VGA connector to the analog pins on the DVI connector.

Does anyone else have any comments on this? it wouldn't suprise me if some manufacturer had done this as a propietry thing but I really think if it was as common as the article asserts i'd have seen it elsewhere by now. Plugwash (talk) 13:15, 19 November 2009 (UTC)

Minimum Frequency

The same VGA cable can be used with a variety of supported VGA resolutions, ranging from 640x400px @70 Hz...

Shouldn't that read 60Hz? —Preceding unsigned comment added by 142.179.217.154 (talk) 00:34, 19 September 2010 (UTC)

Hotpluggable

I think this needs a citation. The VGA interface is not engineered to be hotpluggable (so that the user can connect or disconnect the output device while the host is running),

I cannot confirm this with any source besides wikipedia at this time. — Preceding unsigned comment added by Athomsfere (talk • contribs) 03:08, 24 September 2013 (UTC)

On my laptop (Lenovo T400, Debian 7.2, Gnome3 ) I could connect a VGA monitor and it would detect and enlarge my desktop to fit. that seems hot-plugable to me.118.90.21.181 (talk) 04:35, 11 October 2015 (UTC)

Combine pages?

Shouldn't this page be combined with the VGA (http://en.wikipedia.org/wiki/VGA) page? See http://en.wikipedia.org/wiki/Digital_Visual_Interface for an example. If not, VGA should direct to a disambiguation page, not direct to the above link.76.2.89.37 (talk) 17:31, 12 April 2010 (UTC)

I vote no, the VGA page describes PC expansion cards, as it should, you might have a case for this page to be renamed to 'VGA Interface', but I think the 'VGA connector' is close enough.Jasen betts (talk) 04:55, 11 October 2015 (UTC)

Pinout image is backwards

FYI the pinout numbering is backwards on the image on this page — Preceding unsigned comment added by Mekozloski (talk • contribs) 14:01, 8 December 2015 (UTC)

Most devices still include VGA connectors ...

It seems to me that many include the VGA signals in the DVI connector, and supply the appropriate adapter. Does that count as including a VGA connector? Gah4 (talk) 19:43, 6 September 2017 (UTC)

IBM

There seems to be edit warring regarding redirect vs. pipe. From WP:NOTBROKE the redirect is preferred except for a listed set of reasons. Seems to me that the exceptions don't apply, so that it should be IBM, but I don't want to add to the war. Someone please settle this. Gah4 (talk) 05:32, 28 September 2017 (UTC)

RGB connector?

Hi. I don't know why the RGB connector redirects to VGA. On most computers RGB connector is usually a DSUB 9, and works mainly in so called TV modes (e.g. other freq. that VGA). Also the most popular nowadays RGB connector is probably the SCART interface which usually isn't easily interfaced to VGA monitors... — Preceding unsigned comment added by 89.72.65.224 (talk) 12:38, 17 January 2018 (UTC)

Thanks for calling it to attention. In past decades I have used several kinds of plug to carry RGB signals, and there are many more beyond my experience, so I have redirected it to Component video#RGB analog component video. Perhaps someone will have a better idea. Jim.henderson (talk) 23:32, 21 January 2018 (UTC)

I believe that the VGA connector is now often used as a connector for RGB signals, even if not VGA. But yes, there were 9 pin connectors used for CGA and EGA earlier. The TV I have, has a VGA input that can also be used as a third component video input. Many video processors use the VGA style connector for other types of video signals. Gah4 (talk) 03:11, 22 January 2018 (UTC)

...and to add further confusion, the term "RGB monitor" or "RGB connector" in the old IBM PC-compatible sense usually refers to a TTL digital signal, generally 3-bit RGB, 4-bit RGBI, or 6-bit RrGgBb. VGA connectors were usually referred to more as "analog video" (sometimes "analog color", but that would technically have been a misnomer as VGA also supported analog greyscale/monochrome displays too). 46.208.118.185 (talk) 16:44, 11 July 2018 (UTC)

Paragraph in lede, unreferenced and also not in body

"Although many devices still include VGA connectors, and VGA generally coexisted with the DVI standard, VGA and DVI are both being rapidly phased out in favor of the newer and more compact HDMI and DisplayPort interface connectors."

This needs citations and expansion. 04:43, 30 May 2017 (UTC) — Preceding unsigned comment added by 131.191.60.228 (talk)

I suppose, but DisplayPort, miniDisplayPort, and HDMI to VGA adapters are readily available. (With active circuitry inside.) The other direction is harder, so many devices have VGA inputs, while VGA outputs are being phased out. Gah4 (talk) 19:55, 11 September 2017 (UTC)

Heck, (mini) Displayport can just output analogue VGA directly anyhow, so the converters for that are entirely passive, the same as for HDMI and DVI. It's mainly HDMI > VGA (or the reverse) that's the issue. 46.208.118.185 (talk) 16:45, 11 July 2018 (UTC)

Monitor ID pins?

Anyone know how they worked / what information they transmitted originally? I'm having a bit of trouble finding out. Not anything important, just curiosity, but it's strange to not be able to find that data. The modern I2C setup for DCC is fairly well known, but how did it operate back in the day? I know there was a way for the card to sense whether a colour or monochrome display was connected (and alter its output accordingly - monochrome VGAs only had the Green input connected and ignored the Red and Blue, so software/the card BIOS had to adapt accordingly), but what other options would have existed amongst the 8-option codespace? "Nothing connected" is presumably 0 (000), Monochrome 1 (001), Colour 2 (010)... but the other five?

I expect the 8514(A) / XGA and maybe even IBM's eventual own SVGA monitors probably returned different codes, and maybe the XGA2...? SXGA? Others? Portrait orientation, even? 46.208.118.185 (talk) 16:50, 11 July 2018 (UTC)