Well, I guess the title says it all, after spending a lot of time reading Documentations, Specifications, Forums.. and hunting for testers , I finally got tehmachacker (thank you) to test a modified BIOS, and as expected, it worked.

This is the issue that intends this mod to fix:
http://forum.insanelymac.com/index.php?showtopic=78235

Basically, what I'm doing is modifying and fixing errors in the DSDT; removing aliases for the "processor" devices, because the ACPIPlatform kext doesn't like them and treat them as other CPUs.. (it's written for Macs, and Apple doesn't use that in their Firmware's ACPI Tables, actually I don't see why we need them, well..)
I for example change this:

into:

Sometimes I have to fix more stuff.. you should know that when you try to compile your DSDT.

So if you want to get a fixed BIOS, you can PM me post your request here, included with:

• a direct link to the BIOS file,
• your PC specs (CPU, Chipset and Graphics Card),
• and a description of the issues.

Don't PM me with requests, post them in this thread.

You will find some of the modified BIOSes here.

Keep in mind that I take no responsibility for a bad flash or if anything goes wrong..