Power Mac MT G3/300 Facts at a Glance
- G3 (750), 333 MHz
- Bus Speed: 66 MHz
- L2 Cache: 1 MB, backside @167 MHz
- Installed RAM: 128 MB (768 MBMax)
- RAM Slots: 3, 168-pin SDRAM
- Min RAM Speed: 10 ns
- Installed VRAM: 6 MBSGRAM (Max 6 MB)
- Drive: 9.0 GBUltra/Wide SCSI
- CD Drive: 24X
- Removable Drives: Floppy Drive, Zip Drive
- Networking: 10baseT (other options available)
- Slots: 3 PCI, 1 COMM
- Drive Bays: 2 external
- Additional Ports: ADB, 2 Serial - Printer & Modem
- Supported MacOS: 8.1 - 10
- Introduced: 8/98
- Discontinued: 12/98
- Initial Retail Price: $3,000
- Has Personality card with audio/video in/out
- ATI 3D Rage Pro graphics accelerator
- Internal Zip drive takes up one drive bay
- There was a DVD drive option
- Optional 56K internal modem
PowerMac Upgrade & Troubleshooting
The 333 MHz G3 PowerMacs were a follow-on generation to the
successful 233 & 266 MHz one. They made their appearance in
the summer of 1998 and were discontinued in the last few weeks of
the same year.
The machine came in mini-tower form factor and there were both standard
models and build-to-order options.
The G3 chip found in the 333 Mhz Tower was
a faster version of the PowerPC processor. It's speed was enhanced
because the L2 cache resides on a dedicated backside bus running
at 167 Mhz, between processor and cache. Previously L2 cache performance
was limited by the speed of the main logic board bus which runs
at a much slower speed.
The processor and cache reside in on a removable card that
fits into a PC type Zif socket making it easy to replace with a
faster processor. The main system bus of these G3 machines runs
at 66Mhz (the previous pre-G3 Macs ran at 50Mhz). The G3/333 MT
comes with 128 MB of SDRAM, expandable to 768 MB using the 3 DIMM
The graphics controller is the ATI 3D Rage Pro Turbo. The
machine came standard with 6 MB SGRAM graphics memory (the maximum),
which allows for millions of colors (32-bit) at up to 1280 x 1024
There are 3 PCI slots for add-on cards and a proprietary
slot for the included AV personality card.
The hard drive is 9 GB Ultra/Wide SCSI on the Tower (using
a PCI SCSI card...which uses up one of the slots). The CD ROM is
24x, but there was the option of a DVD drive instead.
The Tower machine has one free 5.23" drive bay (the
other is filled with the internal Zip drive) and the machine has
anexternal SCSI connector (5Mbytes per second).
The machine's case is easy to get into and the simplicity
of the new logic-board design make upgrades a snap.