Hey shaanky, thanks for the guide and files, i think i am nearly there (sound and networking are my downfall). I thought i would share my experience to try and help anyone else.

my setup:
Asus P5EVM-HDMI, C2D E6750, EVGA 8800GT, WD SATA 500gb, NEC IDE CD-rom

Bios:
Left it as is, disabled VGA, sata drives are set to IDE, my old IDE CD-rom is unplugged, but i suspect it will be ok under 10.6

Process:
As advertized, i have a 10.5.2 kalyway setup (everything works good) that i have been too afraid to upgrade, so i had to create the DSDT and run the "gfxutil" to get my hex value graphics card. Installed via my snow leopard upgrade disc. (make sure you disable printers and extra fonts, i kept getting errors on my install). I ran the package in the provided files and copied over the extra folder.

Now, thats where trouble started, i kept getting Kernel panics after the first boot. It would run a bit through the setup, crash.. after 10 tries it finally got to the desktop... my suggestion, run safe mode (tab at the chameleon, then use -X) the first boot to let it set its self up, get one good boot and shut down and i think you will be ok. Also try ruining -V verbose mode to see what's going on. and be very patient, it take forever too boot.

i also re-ran DSDT from SL to see if it helped... i dunno if it did. Anyway, it seems to be ok now, no crashes. I also turned off the sleep after 15 mintues as my computer never seems to come back after a snooze.

my problems:

• The network driver worked the first boot or two, it was getting an IP when i watched the verbose boot, but now it doesn't, verbose mode says its missing dependancies or something.
• I've added the vodooHDA kext to no avail... whats odd is my DSDT doesn't have any reference to HDEF in my dsdt.aml file, so i can't apply any patches or anythign too it. so no sound yet.
• The boot take FOREVER

Thanks for the help, i was about to compeltely give up on 10.6 until i saw your post. I am sure with some more reading and help i will be up to speed again.