"The G3 came in either a mini-tower case (similar to that of the 8600 & 9600, but shorter) or a 7300-style desktop case, and operated at either 233 or 266 MHz, with a 512 KB backside cache operating at 117 and 133 MHz, respectively. The PowerMac G3 Desktop, available at 233 or 266 MHz came with 16-bit Audio In and Out on a separate "personality" card and an internal Zip drive (The Gossomer motherboard was so small that the main HD could be mounted on the floor of the case, leaving room for the Zip, and an additional half-height drive).

The G3 MiniTower model, which initially was only available at 266 MHz, had a different personality card, which offered all the features of the desktop card, plus 4 MB of VRAM (expandable to 6 MB) and S-Video In and Out. The Gossamer motherboard had 3 industry-standard SDRAM slots, allowing for 384 MB of RAM, but due to the height restrictions of the case, the G3 Desktop could not hold 128 MB modules, giving it a maximum of 192 MB. In early 1998, Apple made a 233 MHz tower model available, and added a host of new add-on features for all models including a 4 GB fast/wide SCSI disk, and a faster graphics card.

In March 1998, Apple added a 300 MHz option on all built-to-order machines, as well as a dual-SCSI configuration, with RAID software, and an optional DVD-ROM drive. (A 3rd-party solution were required for MPEG-2 video playback.) A 333 MHz version was made available in September 1998. The PowerMac G3 was discontinued in January 1999, when it was replaced by the "Blue" G3." (picture credits: Apple Computer, John Greenleigh/Flipside Studios)

This byte of Apple history from Wired's, "30 Years of Apple Products."