@Kyle: I have this same mobo but it shipped with AMIBIOS version 0802. I saw the _PSS error until I enabled the "AMD Cool'n'Quiet Function" in the BIOS. While the printed manual isn't helpful, the built-in BIOS help specifically says that this enables generation of ACPI _PSS objects (and a few others).
@Kyle: I have this same mobo but it shipped with AMIBIOS version 0802. I saw the _PSS error until I enabled the "AMD Cool'n'Quiet Function" in the BIOS. While the printed manual isn't helpful, the built-in BIOS help specifically says that this enables generation of ACPI _PSS objects (and a few others).