What are the major differences between the iMac G4 "Flat Panel" and the Power Macintosh G4 models?

One substantial difference between the iMac G4 and the Power Macintosh G4 models is apparent with even a quick glance at the respective systems.

Photo Credit: Apple, Inc. (iMac G4 - Left, Power Mac G4 MDD - Right, Not to Scale)

There is a huge amount of variation between Power Macintosh G4 models as the series was sold for five years -- the photo above is of the "Mirrored Drive Doors" system sold from 2002-2003 -- but in general, the primary differences between the iMac G4 and the Power Macintosh G4 are performance, expandability, and display options.

The iMac G4 models use an attractive 10.6" half-sphere, ice white case with a chromed stainless steel neck that supports a 15 inch, 17 inch, or 20 inch TFT Active Matrix LCD display, whereas the Power Macintosh G4 models use tower case designs and can support a variety of external displays.

Power Macintosh G4 models sold at the same time as particular iMac G4 models were arguably less stylish, but more powerful and much more expandable, with support for multiple drives, multiple expansion cards, and substantially more memory. The tower case design -- with a "fold down" door on the side makes these upgrades a breeze.

The iMac G4, on the other hand, is quite attractive, but it only supports a single hard drive, does not support any expansion cards other than AirPort, and only supports a comparatively modest amount of memory. The compact, all-in-one case design makes upgrading anything beyond the memory in the "lower slot" and the AirPort card a considerable undertaking.

The Power Macintosh G4 models also officially support multiple non-mirrored displays whereas iMac G4 models either cannot support multiple displays or can only do so via hacks.

Please refer to the "Comparison Q&As" from the iMac G4 Q&A and Power Mac G4 Q&A for a review of each line and the Ultimate Mac Comparison feature to compare the details of any iMac G4 to any Power Mac G4 model.