Yes I'm well aware this is an ancient computer. I'm posting this for a mate.
He has an HP Compaq 6710b but I believe the 6730B has the same charger.
INPUT AC 100-240V 50-60Hz
OUTPUT: DC 19V 4.74A 90W
Connector Size:
Internal 5.0mm
External 7.4mm
Anyone have one of these lying around?