The server version of Mac OS X may have different requirements in which the Server forum is better able to answer. This is part of a series of tips from 10.2 through 10.11 (10.6 through 10.11 not mentioned above links as 10.5.8 is the end of the line for all Macs with 10.3 that support up to 10.5.8), which all refer to Mac OS X Client. When determining whether you meet the requirements for updating, see this tip on Mac model and age: Tips on: 10.2 Jaguar (including firmware updated necessary for older Macs to get to 10.2 or higher), 10.3 Panther, 10.4 Tiger, 10.5 Leopard
