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Power Macintosh G3 Computer Features

Here is a list of the hardware features of the Power Macintosh G3 computer. The major features are described more fully later in this note.  

• Microprocessor: PowerPC G3 microprocessor running at a clock frequency of 300 MHz, 350 MHz, or 400 MHz depending on model and configuration. For more information, see PowerPC G3 Microprocessor .
• Cache: 512 KB or 1 MB (depending on model and configuration) of the backside second-level (L2) cache on processor module. The backside cache runs at half the clock frequency of the microprocessor.
• Processor system bus: 64-bit wide data and 32-bit wide address, 100 MHz clock, supporting split address and data tenures.
• RAM: four DIMM slots for industry standard PC-100 SDRAM (synchronous dynamic access memory) DIMMs (dual inline memory modules). Maximum memory with all four slots occupied is 1024 MB. A minimum of 64 MB of RAM is installed in one of the slots. For more information, see RAM DIMMs .
• ROM: New World ROM-in-RAM implementation with 1 MB of boot ROM. For additional information about the ROM, see System ROM and Boot ROM Contents .
• Graphics acceleration: 2D and 3D hardware graphics acceleration using the ATI 3D RAGE 128 GL graphics controller on the 66 MHz 2D/3D accelerated graphics card. Software support through Macintosh QuickDraw 3D and QuickDraw 3D RAVE (rendering acceleration virtual engine) APIs. For more information, see Graphics Card .
• Sound: supports 16 bits/channel stereo input and output on built-in 3.5mm line-level stereo input and output jacks, one built-in speaker. For more information, see Sound System .
• Hard disk drives: one internal Ultra DMA/33 hard disk or Ultra2 SCSI (LVD) hard disk. For more information, see Disk Drives .
• Drive bays: three drive bays, one of which is occupied by an Ultra DMA/33 hard disk or an Ultra2 SCSI (LVD) hard disk. The other two bays are available for adding other devices connected to a PCI controller card. For more information, see Disk Drives .
• CD-ROM drive: internal 24x-speed ATAPI CD-ROM drive.
• DVD-ROM drive: optional ATAPI DVD-ROM drive providing support for 32x-speed CD-ROM and 5x-speed DVD-ROM media, as well as DVD-Video playback with the DVD MPEG2 decode module. The DVD MPEG2 decode module is connected to the PCI graphics card.
• Zip drive: optional 100 MB ATAPI Zip drive. If the Zip drive option is not installed at the time of purchase, data and power connectors are provided to add an ATAPI Zip drive to the system.
• USB ports: two USB ports, described in "USB Ports" (page 28). The computer comes with a USB mouse and a USB keyboard that has two additional USB ports. The additional ports are described under Keyboard and USB .
• ADB port: one ADB port for ADB devices or ColorSync control of Apple monitors. For more information, see ADB Port .
• Ethernet: built in Ethernet port for 10Base-T and 100Base-TX operation with an RJ-45 connector. For more information, see Ethernet Port .
• FireWire ports: two IEEE-1394 high-speed serial FireWire ports, which support transfer rates of 100, 200, and 400 Mbps.
• Modem: optional Apple 56 Kbps modem. The modem supports K56flex and V.90 protocols. For more information, see Internal Modem .
• Keyboard: Apple USB keyboard with function keys and inverted-T cursor motion keys. The keyboard operates as a low-speed (1.5 Mbps) USB device. It also provides a bus-powered USB hub with two USB ports. For more information, see Keyboard .
• Mouse: Apple USB mouse operating as a low-speed (1.5 Mbps) USB device. For more information, see Mouse .
• PCI card expansion slots: three slots for 33 MHz, 32-bit or 64-bit, 12-inch PCI cards; one slot for a 66 MHz 32-bit PCI card, occupied by the accelerated graphics card. For more information, see PCI Expansion Slots .
• Power switch: soft power controlled from the Apple USB keyboard, an ADB keyboard, and the front power button.
• Voltage switch: can be set to either 115 for voltages of 90-132 V or 230 for voltages of 180-264 V, depending on the voltage where the computer is installed. The voltage selection must be set manually.
• Fan speed control: The speed of the fan is thermally controlled and is automatically set to the lowest possible speed to minimize noise. The fan speed varies according to the temperature inside the enclosure. This is a function provided by the fan and is not under software control.
• Energy saving: sleep, startup, and shutdown scheduling can be controlled with an Energy Saver control panel.