I located Intel's datasheet for its Mobile Intel 945 Express Chipset Family and spent eight hours reading in it. (These 482 pages offer a lot of material.)
I found some details which may be relevant for the buggy screen blanking happening with NetBSD-current on the Asus Eeepc: PCI device numbers on specific chipset functions and interactions with LVDS devices, including DDC and EDID information.
And before I forget it again: the i945GSE variant is designed for the Intel Atom N270; it is almost (no Analog TV MacroVision) compatible with the i945GMS which in turn is almost compatible with the i945GM/GME, except for:
Did I ever wanted to read about "Legacy DOS/Video/BIOS Areas" again? Not really, but it appears they are still fully supported by current chipsets. Wow.
Even more "Wow!" is what 2D/3D graphics capabilities are implemented in these chipsets.