Comment 236 for bug 22336

csim says:

"I noticed the following message during boot:

ACPI: Looking for DSDT ... not found!

So i went on installing IASL and looking at what's wrong with the DSDT, when i compiled the resulting dsdt.dsl file, it gave me 9 errors and 23 warnings.

http://gentoo-wiki.com/HOWTO_Fix_Common_ACPI_Problems

I found out that by replacing all _T_0 with T_0, _T_1 with T_1 and _T_2 with T_2 would fix the errors and it did! Now i only had 23 warnings, i was only able to fix 2, since i wasn't sure about the other ones."