Belkin USB 4 port PCI card prevents G4 deep sleep

Belkin has confirmed that their USB 4 port PCI card will not allow the G4 450 (and later models) to fully shut down the fan and PCI bus: "The problem has been duplicated in the lab. The PCI power only turns off if all installed PCI cards support this mode, a component of Power Manager 2.0. The Belkin F5U006-UNV does not support this mode (which also seems to be the case for other competing brands). When these cards are installed on the G4 450, the computer goes to sleep, but it only powers down the hard drive and the display; the PCI bus and the fan are left on."