If you want to boot one without a good battery, you need a later PowerBook AC adapter, one that puts out at least 2 amps. I use a model M5652, which is 3.0 Amps at 7.5 Volts. It's still not as reliable as having a good battery. The surge of power needed to spin up the HD is too much for the original AC adapter. However, once booted, a non-backlit portable draws a miserly 6 Watts. Not bad for a Mac twice as fast as an SE.