If you're not sure which one you have, there are two Apple Tech Info Library articles that will help, #24604 and #58328. There are several PowerBook G3s, released at various times since October 1997. To check your Mac's processor speed, use the Apple System Profiler program (it should be in the Apple menu). Some Mac models have different expansion options for the same model number. Compare the numbers that follow to those in the Network Options List section that follows. To determine your expansion capabilities, start with your general system type (Apple-brand Desktop, Clone Desktop, or Portable), then find the model name and number. Most Macs have multiple expansion options, but note that you only need to use one of them.

The following list attempts to detail Ethernet adapter options for all Mac models. Once you know your options, see the Finding Products section for help locating a reseller that would have the adapter you need. Therefore, if you go shopping for an Ethernet adapter, it needs to be one of those types (Nubus, 7' Nubus, PDS, or a transceiver) to work with your Quadra 650. This means that any of those Quadra models, including the 650, supports options 4, 5, 6, and 11. If you have a Quadra 650, move down the list to Quadras, which shows this line: The options appear by number, which you then compare to the adapter list that follows. This page lists Mac models and their Ethernet options, either built-in or available through an Ethernet adapter. While new Mac models (iMac, G4 etc.) include Ethernet support built-in, earlier Macs can be trickier to get connected to Ethernet. Finding Ethernet adapters for non-Ethernet Macs

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