These are the steps show you how to extract the original DSDT of your system in Ubuntu. After this, you need to EDIT it in order to use properly with Hackintosh systems.
1. Download Ubuntu Live CD from Ubuntu web site:
2. Burn and boot from CD. Choose the 1st option, run without installing.
3. You will be in the Ubuntu desktop as user ubuntu with a home folder of /home/ubuntu.
4. Select white Ubuntu icon called Dash Home (located at the top left), enter the letter ‘t’ or the word ‘term’ in the Search bar to reveal the Terminal. Launch the Terminal and type:
sudo cat /sys/firmware/acpi/tables/DSDT > dsdt.aml
Now you’ll have it in your home folder.
5. You can save the file to a USB flash drive and transfer to OSX for future editing or upload it to the forum
Credit to minusgrad, robbish @ tonymacx86.com