X², TW2004, Aquamark 3
X²

When core frequency matters, the GeCube is able to ever so slightly pull away (but it's within a margin of error), dropping off, again ever so slightly, when we become bandwidth limited at the higher resolution.
TW2004

We're seeing the same thing again with Tiger Woods 2004, a fairly shader heavy title. There's not much between the two 9600XTs at the preferred median setting, making it too close to call.
Aquamark 3

Again, an initial win for the clock boosted GeCube, before the PowerColor claws it back later on. Performance as expected and no bad thing. Our final couple of game tests now.