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I have an old laptop which the display is removed. So I was wondering if there is any way to make an adapter for DVI to use the existing 2x15 pin LCD plug.

This is what the manual says about the plug:

The 15-pin D-sub monitor port supports a standard VGA-compatible device such as a monitor or projector to allow viewing on a larger external display.

Essentially I want to achieve this:

Flowchart of display signal

And this is what the plug looks like if that would be of interest:

LCD plug from above

LCD plug from front

I have the male plug which fits into the female plug shown in the images. The male plug has cables attached to it. The cables that ran through the display housing to the actual display.

What I would like to know by asking this question is:

  1. Can it be done?
  2. If yes: Will I need to make some sort of signal conversion or will it be enough to simply connect the cables to a female DVI?
  3. If no: Why? Is there an alternative way?

Also, I will gladly accept some feedback on which tags and terminology to use when it comes to this subject.

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    \$\begingroup\$ Do you have any details on the display in question? Without documentation it is hard to say whether it can be done or not. That appears to be an HDMI connector at the edge of the field of view. If so, you could get DVI into there via a DVI to HDMI converter. \$\endgroup\$ – tallganglyguy Oct 16 '11 at 15:00
  • \$\begingroup\$ I'm afraid not. I couldn't even find the manual for that computer on the manufacturers site. The thing is, since it's a laptop I want to be able to plug in a display to the primary display, to avoid problems with having a secondary external display. So I guess the problem comes down to not being able to figure out what the different pins are for? And I won't be able to figure it out without any kind of documentation? \$\endgroup\$ – rzetterberg Oct 16 '11 at 16:13
  • \$\begingroup\$ Actually I found something about the LCD plug, look at the top of my question. I edited it and added the information. \$\endgroup\$ – rzetterberg Oct 16 '11 at 16:17
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The reference in the manual to a 15 pin D-sub connector relates to the provision of video on a socket on the outside of the laptop for connection of an external display. This has nothing to do with the internal interface to the internal LCD.

I suspect that the easiest "fix" is to decide how to get your external display to fully mirror the internal (dead ) one and then produce / acquire the simple program required to set this up properly both at turn on and any time you enter a selected key sequence.

TGG has mention what appears to be an HDMI connector in your LCD photo. If this is what it is and if it intended for video interfacing to the display it will be the easiest way of achieving what you want to do.

There is no certainty at all that the interface to your LCD is DVI - it probably isn't. If the laptop is 'somewhat old'. that MAY be a VGA connector.

LCD displays have used DVI, VGA and many use

Discussion here on what Dell Inspiron uses.

Parlez vous Francais?
This page is in French They claim to have achieved a working connection to a laptop LCD display. Wrong direction for you and only relates to that model or similar but useful.

This page says

  • LVDS is the signaling system used with most flat panels in laptops. FPD-Links (Flat Panel Display Links) are the actual interface (like DVI) that most laptops use to connect LCD panels to graphics boards. FPD uses LVDS.

    Another interface used in modern laptops is called OpenLDI which also uses LVDS signaling.

You don't want to know :-).

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  • \$\begingroup\$ Thanks for clearing this out for me! I suspected this would be something too much of a fuss to solve for this hobby project. I will probably just use the external VGA and force the mirroring with the OS. Or if there's a setting in the BIOS to force the external VGA to be the primary display. \$\endgroup\$ – rzetterberg Oct 16 '11 at 17:48
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There's no guarantee that the interface from a laptop's graphics chip to the internal display panel is the same interface as the one to the external display. The part from the manual:

The 15-pin D-sub monitor port supports a standard VGA-compatible device such as a monitor or projector to allow viewing on a larger external display.

Is almost certainly not talking about this internal connector (which has twice as many pins!), but instead talking about a 15-pin D-sub on the exterior of the laptop. You know how there are a lot of graphics cards with one DVI output and one VGA output , both of which can drive a display? Laptops would use the DVI interface for the internal and the VGA interface for the external. There is no implication of compatibility or interchangeability between the two.

Internal monitor interfaces were DVI-based for a little bit several years ago, but are now mostly LVDS-based interfaces. There is not enough information to tell which from your question, but in general, odds are that that connector is LVDS, does not have a standard pinout, and does not have VGA or DVI signals.

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  • \$\begingroup\$ Yes, likely LVDS or an older direct to lcd panel interface. Even LVDS has many options, so finding the right panel to match is tricky. \$\endgroup\$ – kenny Oct 16 '11 at 18:54
  • \$\begingroup\$ The issue is that it's nontrivial to convert LVDS to DVI. \$\endgroup\$ – Mike DeSimone Oct 16 '11 at 23:39

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