Evolva, our only Direct3D benchmark, is also behaving like the two games displayed above. The benefit of the overclocking is clearly visible.

The bump mapping version of Evolva doesn't show as high frame rates, but it benefits from the overclocking even more than the other games.

It may well be that your GeForce2 Ultra card will not have memory that is quite as overclockable as this. However, every percent increase of the memory clock will directly translate in frame rate as long as you play at high resolutions and possibly even true color.