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I stripped this VGA cable. It only has 5 wires. One is just single copper strand.

Is this normal? If so what would be the pinout?

VGA wire picture

JRE
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Kalash Changal
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    That is "just barely" a VGA cable -- no coax for the RGB video signals, no EDID, etc. Might work on a low-res monitor over short distances, nothing more. – Dave Tweed Nov 10 '23 at 12:49

5 Answers5

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You should review the VGA connector pinout here:

https://en.wikipedia.org/wiki/VGA_connector

With an ohmmeter you should be able to determine the pin that each wire is connected to - this is an electrical engineering forum after all. From there it's a simple correlation with the VGA connector page to determine each function.

Not knowing what it used to be attached to, it is impossible for me to make a determination if it is, as you say, normal, or otherwise.

Timothy
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Yes, five wires plus a ground wire is normal. VGA has three wires for RGB, two for H- and V-sync, and one (usually blank) for ground. You can see the pinout in this question: Why does VGA have so many ground pins (compared to DVI-I for example)?

Paul
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    It lacks support for DDC which means no EDID, so don’t be surprised if the host computer doesn’t detect the capabilities of the monitor correctly… – jcaron Nov 10 '23 at 13:12
  • Correct, this is the "original" configuration without DDC. – Paul Nov 10 '23 at 13:37
  • I'd say five wires is not normal. For video, at least there should be three coaxial cables. The blue colour indicates it should be new enough to support DDC but it clearly doesn't. – Justme Nov 13 '23 at 20:32
  • @Justme it was five plus a blank one, enough for basic vga without ddc – Paul Nov 13 '23 at 20:57
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That might barely work but it is very poor quality cable.

Usually video signals are transmitted in a coaxial cable.

There are also DDC wires missing so monitor detection won't work.

I would say it is not normal and you should expect better from a VGA cable.

Pinout is unknown, we can't say how the wires are connected, only guess. RGB coule be the RGB signals and bare wire could be ground. Other 2 wires are sync signals.

Justme
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The core of VGA that has remained consistent over the years consists of.

  • 5 main signal lines carrying the video signal, carrying the RGB colour components and the H and V sync lines.
  • 5 ground pins. Nominally each ground pin is associated with one of the main signals, but in practice many cables link them all together.

That leaves 5 pins remaining. Originally 4 of them were used for a monitor ID, and the remaining pin was blocked off in the socket and omitted in the plug. Later the pins were repurposed, the formerly blocked off pin became a 5V power line, while two of the four monitor ID lines were repurposed for DDC communication to detect a much wider variety of monitors.

A decent cable will use miniature coax for at least the RGB signals. Some will also use it for the H and V signals. A decent modern VGA cable will also have wires for the DDC lines, otherwise your computer will not be able to detect what monitor is is connected to.

As for your cable it looks like the manufacturer has cheaped out and done the bare minimum to get some kind of video signal through. 5 wires for RGBHV and a single ground wire. No attempt at impedance control for the RGB signals. No additional signal lines.

Peter Green
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Just because it uses a DE-15 plug it doesn't mean it's a VGA cable. A DE-15 plug is general-purpose. It existed before VGA was invented. VGA adopted that plug as well as other plugs. But that plug can and has been used before VGA for other purposes as well. Chances are that that cable was for one of those other purposes.

Davide Andrea
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