Hello shadow3k
My computer is very similar to yours,

AM2+ MSI K9A2 CF (790X+sb600)
AMD Phenom 9950 2.6 BE
ATI Gigabyte HD4870 512MB
SEGATE 500GB SATA II

I've started the install and it's recognize my SATA Drives!
I wish you know which settings you changed in the BIOS if any?

and how did you make your card to work? how can make my 4870 to work in LawlessPPC? I've got the 10.5.4 version...

Thanks for your help!