This is by far the best screen saver I've found that works well with an ATI Rage 128 Pro graphics card. The animation is smooth even when the whole screen is filled with the "spread" patterns.
The only thing this screensaver lacks is customizability, which isn't really a necessity.
533 MHz Power Mac G4 (PowerMac3,4)
ATY,Rage128Pro chipset with 16 MB VRAM
Mac OS X v10.5.8