Yep. It's not so much a custom graphics chip, as the companies who make the LCDs never standardising the connection. lcds in a laptop are really minimalist, there was only one small circuitboard you could get to in my old dell, and I think that was actually just to power the backlight. Other than that it's just a ribon cable, all the actual stuff is in the keyboard half.
I've seen loads of attempts to use laptop lcds, and I've never seen one actually succeed.