I don't suppose anyone has tested this with AMD cards yet? I believe I've run into the same issue with a Radeon E8950 in a Precision M6800. The eDP screen displays the desktop, but the backlight never illuminates. An unfortunate final hurdle after the last two months of research and fabrication to get this far with it. I suppose it makes sense because this particular E8950 was meant for servers where it would never need to activate a backlight. Its datasheet has so far been unobtanium, but I would assume the pins are electrically identical since the cards all have to adhere to the MXM pinout.
