Originally Posted by uman

For Intel northbridges, you typically subtract 2 from the device id of your graphics device (in your case 2e12) to get the device id of the chipset "bridge". See: http://en.wikipedia.org/wiki/Intel_GMA for details.

On both the MacBook X3100 and some HackBooks X3100, there is a device in ioreg called MCHC ("acpi-path" = "IOACPIPlane:/_SB/PCI0/MCHC@0") that is registered against the chipset bridge.

A good source for decoding some of the DSDT mysteries WRT to northbridges is here: http://tracker.coreboot.org/trac/cor.../acpi?rev=4455

-u