No AHCI in laptop bios, thats how it works on my AMD box but i don't have any options to change anything regarding hard drive in laptop.
While booting up from the DVD there is a message:
AppleVIAATADriver: VIA Unknown (CMD 0x170, CTR 0x374, IRQ 15, BM 0x4c58)

Via chipset is VIA VN896. Sata controller is ven_1106&dev_0591, so its 0x05911106. In AppleVIAATA, under PATA i found 0x5711106 which is also my ide/pata controller and i guess its good. But under sata, in the same kext, i was trying to add my sata controller id among the others but it crashes while booting. So that was what i tried.

Ops, i see we are close to something :-) Yes i have USB drive, lacie 80gb. Trying it right now and installer finds it, so i guess i can install leopard on it.

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