I have a Toshiba M11 with exactly the same problem as Pentothal. The screen is LVDS but is not sending an EDID out, if you look under the frame buffer in ioreg with IntelHDGraphicsFB loaded no displays are present. I have tried injecting the EDID through DSDT, Natit and monitor overrides, nothing works. Some of the other Intel framebuffers have EDID override code in them, unfortunately although IntelHDGraphicsFB does have the code it is not used, did try to call it by manually altering the code but that just caused a kernel panic.
I think Pentothal is correct, for us because EDID is not being sent the Framebuffer can't determine the correct timing and ignores the screen