Yup.
1. That system doesn't have enough power supply plugs for 4 drives
2. There's only enough IDE controller in the blue and white for 2 IDE drives
3. And said IDE controller does not have 48-bit LBA, which means it can't see more than 127GB (only recent G4s added the ability for >127GB drives)
4. The IDE controller in Rev. A blue and white G3s is flawed, and works extremely unreliably with any drive it didn't ship with. Rev. B blue G3s do not have this problem.
tooki