Here’s the ACPI DSDT (Darwin-style) for the Gigabyte P55-UD3 Intel LGA 1156 socket mainboard revision 1.0, BIOS version F4i. I’m using it with a Lynnfield Core i7-860 CPU. Created using DSDT Patcher 1e so you may need to recompile it shortening the RTC IO block length from 4 to 2 in case you get a BIOS reset when booting into OSX86 SL (once a 10.0.x XNU kernel supporting the new CPU/stepping is out).
This screenshot shows the Geekbench score for this rig running under 10.5.8. Not too shabby, is it?
By the way I’m not providing any installation support. Please visit the appropriate forums for support.