Ask Max: External USB hard drives - require 2 ports?
Does my PowerBook have to use both USB ports to power an external hard drive? Will the LaCie Mobile 100GB 5400RPM Hard Drive USB 2.0 and FireWire work with a PowerBook? Will it run on either bus power or adaptor? Will it have to use both USB ports? Is FireWire powered as is USB? I bought a WD external HD but it won't mount using one USB port. A USB splitter that will reach both ends of a PowerBook is tough to find.
Some bus-powered USB drives do require two USB ports. Many of the LaCie mobile drives use a special USB-to-power plug cable. The special power plug attaches to one USB port for power and a standard USB cable connects the drive to the computer's other USB port for data transfers. In most cases the FireWire port on your PowerBook will have enough power to operate the LaCie Mobile drive without any assistance, but if FireWire fails to provide enough juice then you can add the special USB power cable. On every G4 PowerBook the FireWire port is near a USB port. That way if you have to use two cables they at least can be next to each other. Also, by using FireWire for the data connection the worst case is you will only have to sacrifice one USB port.