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I'm planning a project of building a 4:3 laptop based on existing (modern) components. As 4:3 displays are not manufactured anymore the idea is to take one from a old laptop, like a thinkpad T60. Then use modern laptop motherboard and components and put all that in a custom shell.

My main worry is that I don't know exactly how the LVDS interface is working. As the modern motherboard is going to be specific to the 16:9 display with which it's going to come along.

I think the LVDS interface is quite standard, though I think there are different 'version', so I guess the customization is probably on the software side?

Do you know how exactly a laptop motherboard is setup to a specific display? Is it coded in the bios? Or is there a LVDS controller chip that has a specific firmware flashed into? Any hints how you would do that?

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The LVDS interface standard should be pretty straight-forward, but it is only that - an interface standard. It only describes, which (and how many, 2 or 4) pairs of wires carry signals from the controller to the LCD panel, and at what voltages. But it does not say what the signal means to the controller or the panel. This is done by the display driver, and is specific to the panel in use (is it 16-bit, or 18-bit, or 24-bit color display; front and back porch requirements for horizontal and vertical scan lines; refresh clock rates and display resolution; etc.). The display driver may implemented be in hardware or in software.

On the other hand, the connection interface does not necessarily mean you are stuck with a specific controller. After all, even an Arduino can produce the signal to drive a VGA display, so you can definitely could find or create a solution to drive your LVDS display... It depends on the board you want to use for your machine, but you have provided no specific information at all.

My final advice is to find the make and model of your LCD panel and look on Ebay for a driver board. Those are to be found for most LCD panels produced in the last 10-15 years, and cost in the range of $ 15 to $70 USD. So find a driver board that fits your LCD and experiment with it. Usually they offer different input signals - RCA, S-Video, VGA, DVI, HDMI, or all of them together. And the LVDS is then how the driver board connects to the display. After you have played around with it a bit, you can see if you can use this same board in your machine (if you remove the unneeded connectors) or just create your own driver on the basis of the first board by using the same parts, but making it fit the format of your new machine....

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  • \$\begingroup\$ Thanks for your reply! Yes those boards are a solution that I thought about. But I would like to use the LVDS interface to leave the other interfaces available. After looking further I found on a thinkpad T60 modding guide that the LCD has EDID (en.wikipedia.org/wiki/Extended_Display_Identification_Data) flashed on chip. I'll look about that in more details. \$\endgroup\$ May 29 '20 at 13:18

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