Power Macintosh Blue & White G3/300 Processor Upgrade And Discussion Page - Performance Of Latest G3 & G4 Processor Upgrades


Power Mac B &W G3/300 Facts at a Glance

  • G3 (750), 300 MHz
  • Bus Speed: 100 MHz
  • L2 Cache: 512K, backside @150 MHz
  • Installed RAM: 64 MB (1024 MB Max)
  • RAM Slots: 4, 168-pin SDRAM
  • Min RAM Speed: 10 ns (100 MHz)
  • Installed VRAM: 16 MB (Max 16 MB)
  • Drive: 6.0 GB ATA
  • CD Drive: 24X
  • Removable Drives: Zip Drive optional
  • Networking: 10/100BaseT
  • Slots: 4 PCI, 1 COMM
  • Free Drive Bays: 3 - 1 external and 2 internal
  • Additional Ports: ADB, 2 USB, 2 FireWire
  • Supported MacOS: 8.5.1 - 10
  • Introduced: 1/99
  • Discontinued: 8/99
  • Initial Retail Price: $1,600
  • Current Price
  • ATI 3D Rage GL graphics accelerator
  • Internal Zip drive option
  • There was a DVD drive option
  • Optional 56K internal modem

PowerMac Upgrade & Troubleshooting
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With the advent of the new year 1999 Apple rolled out its next generation of G3 PowerMacs. Designed with the professional Web designer, publishing pro, video editor and 3-D gamer in mind, these high end machines departed in both technology and design from the first generation G3s. Code named Yosemite the computers came in 3 different speeds; 400Mhz, 350Mhz and 300Mhz and in four different models. The system bus on the Yosemite machines is likewise faster than the previous generation and run at 100Mhz (as opposed to 66Mhz) Graphics are handled by a high-end ATI RAGE 128 graphics accelerator and 16MB of SDRAM graphics memory. This made them appropriate for high-end graphics work and, at the time, for superb gaming. Installed memory was 64MB of PC100 SDRAM (3.3-volt, unbuffered, 64-bit-wide, 168-pin, running at 100 MHz). This can be upgraded in each machine up to 1GB using the 4 provided memory slots. Memory from prior Power Macintosh (EDO or FPM RAM) computers cannot be used in the the Blue & White systems.

The Yosemite class machines provide easy access to their insides . The side panel easily swings down when a lever on the side of the machine is manipulated - exposing the innards of the computer. Inside you will find 4 PCI slots (3 empty slots running at 33Mhz (64 -bit) and one special high speed 66Mhz, 32-bit PCI slot that is filled with the ATI RAGE 128 graphics accelerator) and 5 internal drive bays with built in support for the new Ultra ATA drives ( three for 3 1/2-inch hard drives and 2 for 5 1/4-inch drives - CD ROM, Zip, DVD etc.). There is no built in SCSI bus. If you want to add SCSI devices you will have to do so through a PCI card, using up one of your slots. There is also no floppy drive. The new Power Macintosh G3s came standard with a built-in slot to accommodate an internal 56K modem, which supports both the K56flex and V.90 standards. The actual internal modem is an add-on option.

With these machines Apple moved forward to the new connection standards it had committed to. It has eased out SCSI in favor of two 400Mbps firewire ports (for connecting high-speed peripherals such as drives and video) and continued the abandonment of the serial port it started with iMac in favor of two 12Mbps USB ports for connecting low speed devices (such as keyboards, mice etc). In a nod to the past it included one ADB port on the machines so you can connect your old mouse, keyboard, graphics tablet or other ADB device. All machines came with 10/100BaseT Ethernet.

For connecting monitors, these machines moved to the "PC", VGA port standard. If you want to connect an older Mac monitor you'll have to use a VGA-to-Mac adapter. The ATI RAGE 128 graphics accelerator supports up to 1,920- by 1,200-pixel resolution at 32 bits per pixel (millions of colors)

In looks the Yosemite machines took the traditional mini-tower form factor and cover it all with a iMac type frosting made of the same bulletproof plastic found encasing the early iMacs. At each corner is found a sturdy handle, making it easy to move the machines around. If the Yosemite machines weren't as radical a design departure as the iMac was, they were still quite stunning in appearance.

The Yosemite machines shipped with system 8.5.1 installed. OS 8.5.1 fixed some bugs associated with the initial release of 8.5. It also shipped with the same controversial Apple compact USB Keyboard and Apple round USB Mouse found with the original iMac.

Below you will find the MacBench 5.0 results for most of the processor upgrades available for this machine.

** Note that MacBench does not take advantage of the Velocity Engine (AltiVec instructions) of the G4. For AltiVec accelerated applications you can see a 1.4 to 4 times performance improvement over the G3, depending on the application and the functions you are trying to perform.


"But I thought that the G4 was so much faster than the G3?" In some cases it is! For G4 Application specific scores - Click Here

MacBench Absolute Scores

Processor Upgrade Card

MacBench 5.0 Processor Score

Blue & White Power Macintosh G3/300 936
XLR8 MACh Speed MPe G4/400/200/1MB 1186
XLR8 MACh Velocity MPe Dual G4/400/200/1MB
PowerLogix PowerForce G4Z/400/200/1MB 1243
Sonnet Encore G4/400/200/1MB 1252
XLR8 MACh Speed G3Z/400/200/1MB 1314
XLR8 MACh Speed MPe G4/450/225/1MB 1335
XLR8 MACh Velocity MPe Dual G4/450/225/1MB 1335
PowerLogix PowerForce G4Z/450/225/1MB 1398
XLR8 MACh Speed G3Z/450/225/1MB 1478
XLR8 MACh Speed MPe G4/500/250/1MB 1483
XLR8 MACh Velocity MPe Dual G4/500/250/1MB 1483
XLR8 MACh Speed G3Z/466/233/1MB 1531
Sonnet Encore G4/500/250/1MB 1565
XLR8 MACh Speed G3Z/500/250/1MB 1643
Sonnet Encore G3/500/250/1MB 1679
PowerLogix PowerForce G3Z/500/250/1MB 1680

Internal Links

External Links

More information on the G3/300
  • Processor Card Upgrade Index
  • Graphics Card Upgrades Index
  • Upgrades By Machine
  • Hardware Index
  • Older Machine Benchmark Comparisons
  • Processor Upgrade Cards Manufacturers Links
  • Apple's online specs for the G3/300 Desktop
  • LowEndMac's information page for this machine
  • EveryMac's information page for this machine
  • Processor Card Reviews
  • Index of all online Macintosh hardware and software reviews