I was just wondering that. It will be easy to upgrade from a PII to a PIII, they are similar and don’t require special things like different power supply, extra ventilation. It will be like rebuilding your PII system again. You will find a few new connectors on that new power supply, just don’t use them, they are for P4 and newer AMD systems . You will have enough power for your PIII and 4 hard drives by way of speaking, famer past you a nice link for telling witch power supply will suit your needs. Also he knows how to build computers, like I do, buy a case without a power supply and by a separate power supply that suits. Only problem is that it will be way more then 30 US$ .