#mount   -uw  /

#mkdir /Bak_ATI

#mv  /System/Library/Extensions/ATI*.kext /Bak_ATI/

#reboot

Now place the Snow Leopard Boot CD to boot.

• Boot With Snow Leopard CD Boot, when chameleon logo appear, select your Snow leopard partition and type : “arch=i386″ (without quote if you want to boot in 32bit mode, if you don’t enter anything, it will go automatically into 64bit mode. Also remember the BIOS setting if you have set it to 32/64bit) and following on screen.
• Install Snow Leopard Boot Loader
• Click on Go -> Computer -> Snow (name of the disk) -> Extra and copy all Snow Leopard Kexts and Extensions folder from download location to this Extra folder.

• Inject EFI strings for devices (graphics, Ethernet and sound (if available)

Although Mac Gurus don’t like so called EFI Injectors, but if you are new to SL and don’t wana go the detailes of DSDT.aml then check if you could get your graphics, ethernet and audio working through EFI injection using OSX86 Tools. This is the easiest way to get most of the things working (although my sound card ALC888 did not work through this method, so I had to do DSDT method, still doing research to enable sound in this motherboard). Well I agree with Mac Gurus upto some extent in this regard, but my idea is first to run SL without any problem and then do the improvements like creating and editing DSDT.aml for various devices etc.

• Run OSX86 Tools. Click on “Add EFI String/Boot Flag” button. First click on graphics card, from the drop down menu, choose your graphics card, it will give you hexadecimal EFI string in the bottom section. Then click on 2nd icon on top row “Import String to Boot Editor” After that you will have to click on button at the bottom “Apply changes to com.apple.Boot.plist”. Similarly do it for your Audio and Ethernet Strings. A quick tip here, you will not be able to see the effect unless you reboot. So when you next time boot, again check the QE/CI/GL for your graphics (by adding a gadget in dashboard, if you don’t see a clear water waves effect, again run OSX86 Tools, and click on “Enable/Disable Quarts GL” button of upper left side. Enable it. Again reboot and you will get the QE/CI/GL enabled for Nvidia GF8800GT card.

• Open the DSDT Patcher folder, and double click the DSDT Patcher icon. When it say press any key to continue, just enter. Then it will ask you “Which OS to emulate? [0=Darwin, 1=WinXP, 2=WinVista]. Press 0 and enter for Darwin based OS. 99% this gives you a DSDT.dsl file in the same folder of DSDT Patcher. This is a text editor file and we can change it in a text editor (if we need to do it). This patcher already applied the Snow Leopard’s CMOS reset fix for you. So you don’t have to worry about. Pay attention to the text appearing in this program window when it says “Process Completed”. If you get any error or warnings, then contact your best friend (google.com) for the help to remove these errors. If you get 0 error and 0 warnings, its ok to proceed.
• In 2nd step we will edit it if we need to. If you want to edit DSDT.dsl file to have the codes for Ethernet and sound etc. You need to follow this guide.
• Suppose you get no errors and no warnings and you don’t want to edit .dsl file. Next step is to compile this DSDT.dsl file to get a DSDT.aml file. Open the folder which contains the iaslME application. Open the DSDT Patcher folder also which should be having your dsdt.dsl file. Now drag and drop dsdt.dsl file over the iaslMe application icon. It will automatically generate a dsdt.aml file for you and will store it in the “Sessions” folder. Go to DSDT Patcher folder, then Open Session folder, then a folder which will be having most recent date and time as name of the folder. You will find two files; one will be dsdt.aml and other will be log.
• Now you right click on dsdt.aml and choose Get info -> Name and Extension. Change the name of the file from dsdt.aml to DSDT.aml. (as this file name is case sensitive). Now copy this file and past it in the Extra folder. It might ask you to authenticate it with administrative password.
• Final Step: Remove the Snow Installation DVD and reboot the system. Again press Del key go to BIOS and load the recommended settings for the last time (as you have already put DSDT.aml file in Extra folder which is having CMOS reset fix) and then save and exit from BIOS. Switch off your computer. Switch it on and you will get the Snow Leopard fully working (hopefully).

If by using DSDT.aml method still you are unable to use some of your devices, then you need to convert DSDT.aml into DSDT.dsl using iaslMe (just drop the DSDT.aml over the application icon) and edit the DSDT.dsl using text editor. For details I would recommend searching google for your problem, as I am also new in this particular technique and will not be able to help you much. Suggested links are in my reference section.