Please note that all models mentioned in these Q&As have been discontinued.

What are the major differences between the Mac mini G4 and the eMac?

The Mac mini G4 and eMac use completely different case types, so the physical difference becomes obvious with a quick glance at the systems. The eMac uses a design with the computer and a 17.0" (16.0" viewable area) CRT display in a 50 pound all-in-one enclosure.

The Mac mini G4, on the other hand, uses an elegant 2.9 pound, 6.5 inch square, two inch tall cuboid enclosure without an integrated display.

However, there are significant technical similarities between the Mac mini G4 and the eMac G4/1.25 (USB 2.0) available at the same time.

Both systems use similar logic board designs with the same type of "G4" processors (PowerPC 7447a), memory (PC2700 DDR SDRAM), and video systems (ATI Radeon 9200).

Please note that both of these images are courtesy of Apple, Inc and are not to scale.

How fast is the Mac mini G4 compared to the iMac G5 and eMac?

The always excellent MacInTouch [no longer online] and Bare Feats posted in-depth benchmarks comparing the Mac mini G4 to the iMac G5, eMac, and a handful of other systems of similar vintage. In general, the Mac mini tends to hold its own compared to the iMac G5 and eMac on most tasks, suffering on disk-intensive tasks where the slower drive used by the entry-level Mac mini is a substantial factor.

Overall, MacInTouch concludes:

For far less money than an iMac [G5] or even an eMac costs, you get excellent performance, silent operation and the ability to drive a big beautiful monitor of your own choosing. . .

The mini's one weakness is disk performance, which may make the eMac a better choice for video, database and multimedia work, but it shouldn't be an issue in too many applications. For general home or office use, the mini is perfect.

Likewise, Bare Feats concludes:

The Mac mini is a credible performer when running 'normal' productivity applications. Unless you are a speed fanatic with demanding, resource hungry applications, you should be very happy with your mini.