Hi, I have an AMD Dual Core CPU and it works fine with ACPI with just PSD=ACPI.PSD /SMP /APIC
The only problem is that sometimes boot freezes just before the DHCP and it requires a cold reset to restart. It is something related to USB, I think, because when the problem occurs I see the indicator led on the USB keyboard switching on and off. Sometimes several reboots are required to get the WPS. Except this, both the CPUs work fine.