Prompted by a discussion on one of the eCS newsgroups, I tried my Asus M2N-SLI Deluxe system (nVidia nForce 570) with PSD=ACPI.PSD /SMP /PIC and was surprised to find that it works, despite the instructions in Pasha's ACPI docs. that such systems must run in APIC mode.
The machine runs with /SMP /APIC, but the LSILogic SCSI adapter is then inaccessible. I have tried REMAPping the SCSI adapter's high IRQs (17 and 18) to low IRQs, but without success: the SCSI adapter is still not recognized.
Using /SMP /APIC /!NOD enables the SCSI adapter, but I have been told that this is the equivalent of running in /PIC mode anyway.