i ran the powerlogix g3 in my beige and then put the g4 in because my brother and i traded. he wants to push the bus back up to 100Mhz.... G4 screams compared to the g3 when having more than one app open.

as for in os 9, I did have the lock up problem with both cpus and it was an ATi driver. I disabled those extensions and installed the drivers off of the ATi CD that came with the card and now everything runs PERFECTLY.

Also games like UT 2k4 and Call of Duty use altivec and having the g4 makes the game playable.