Can this even be done? The Gigabit Ethernet uses a 100mhz bus, the Digital Audio and Quicksilver use 133mhz bus. If it does work, you won't get 733mhz from it because 733 isn't a multiple of 100. You'll get 550 at best, if it works at all and if 550 is all you're going to get then you'll be better off with a dual 450 or 500 CPU card that was made for the Gigabit Ethernet.