Click for Wireless Networking Adapters and Bases!
Click for Wireless Adapters and Bases!

A Click shows your site support to my Sponsors

Accelerate Your Mac! - the source for performance news and reviews
The Source for Mac Performance News and Reviews

XLR8 G4z BoxRating
Review: XLR8's MACh Speed G4zTM
G4 CPU Upgrade for AIO/Beige/B&W G3s
By Mike
Published: 11/22/99
400MHz G4 CPU Upgrade Review
Intro | Benchmarks  | Appl. Tests | Software Controls  | Installation | Specs/Design | Summary
XLR8 's MACh Speed G4z allows AIO, Beige and B&W G3s to upgrade to the same CPU as in Apple's latest Yikes (PCI based) and Sawtooth (AGP slot) models. It will also work in their CarrierZIF (ZIF socketed) cards to allow many older Macs (with CPU card slots) to also run a G4 CPU. Although the price is not cheap (about $880 at the time of this review), my tests show it provides MHz/MHz about the same performance as my new G4 Sawtooth Mac in many applications and certainly exceeds the $1600 Yikes G4/350 performance. Granted the Sawtooth has an AGP slot, Airport compatibility, ATA/66 and internal Firewire, but then it costs $2500 or so. [Update: After this review was published, in early December 1999 Apple replaced the the Yikes G4 system with a Sawtooth/AGP motherboard based system as the low end model. DVD and a Rage128 Pro (faster clock speed with digital LCD connector) are also standard at $1599 See the Apple store for details. Prices (and features) of new Macs change over time of course, so check the Apple Store for current model details.]

As regular readers know, both my B&W G3s have the v1.1 firmware which prevents a G4 CPU from booting. XLR8's Firmware Updater solves this issue however as noted on the installation page.

Despite some claims of supercomputer performance with a G4 CPU, without software that takes advantage of the Altivec core, a G4 seems to run applications no faster than a G3 CPU of the same speed (all other factors being equal) as shown on the application tests page. What's puzzling is that again I've seen where the faster FPU of the G4, even in OS 9 with its limited Altivec support, does not provide any measurable benefit in many current CPU/FPU bound applications. I expected at least some small gain, but in some cases the G4 was actually a second or so slower than the same speed G3 CPU in some older apps tests. (This was repeatable, although such a small a difference is likely within the run to run variation of most application tests).

Applications with Altivec support like SoundJam MP and Photoshop 5.5 (with Adobe's Altivec extensions) do show a marked advantage with the G4 CPU however. Even though there are known bugs in Adobe's first Altivec extensions, I did see increases of up to 3.44x on some filter operations - very impressive gains from the same speed CPU. SoundJam MP showed an appx. 50% boost from the G4 over the same speed G3 CPU. Even the latest OpenGL 1.1.2 contains some Altivec optimizations.

(Update: Although not shown in this review, I later tested G4s vs G3s using iMovie; timing now long it takes to complete the export/output to a Quicktime Movie. A G4 is almost twice as fast at this task as the same speed G3. If you do a lot of video compression or output of DV to Quicktime movies, a G4 CPU can pay for itself fairly quickly.)

About OS 9 and G4 Upgrades: [NOTE: This review was written long before OS 9.1 was released - OS 9.1 does not have the extensions below (doesn't need them) and will remove them if they exist during an OS 9.1 update. For see this related article on OS 9.1.] As noted on my Nov 13th 1999 weekend news page, if you install OS 9.0 (or 9.04) on a G4 CPU upgraded Mac, the 4 OS 9 Altivec extensions are not normally installed. (Note: These 4 extensions are only a part of OS 9.0 and OS 9.04 - not OS 9.1) These 4 extensions are:

  • vBasicOps
  • vBigNum
  • vectorOps
  • vMathLib

I'm told selecting a customized OS 9 install and choosing a Universal OS 9 installation will install them, but a better way may be using Tome Viewer as a way to extract specific files from installers. Point Tome Viewer at Mac OS 9:Software Installers:System Software:Mac OS 9 Additions:Tome.
The other Altivec support software present on Apple G4 systems is contained in the Adobe folder inside the 'Application Support' folder of the System/Extensions folder. This of course is not present on the OS 9 CD. As noted in the front page news here recently, Powerlogix reported that Adobe will be releasing their Altivec extensions for Photoshop 5.5 in the future. XLR8 ships a Photoshop v3/4 Altivec extension with their G4 CPU Upgrades.

As regular readers know from my previous reviews and comments from the front page news, the XLR8 G4 ZIF upgrades can also be used in their CarrierZIFTM card for many older Macs with CPU card slots. XLR8 also has a Trade-Up discount program for owners of XLR8 G3 CPU cards (MAChCarrier or MAChSpeed models - see their trade-up page for all the details).

Review Tests/Ratings:

  1. BenchMark Performance: Includes MacBench 5.0, Walker 1.1, G4Timedemo, Memory Bench, Stream, GaugePro and RaveBench tests results. Although I'm no fan of Bytemark DR/3, results with it are not shown due to a compatibility issue (scores of 0). I include results with of a stock B&W G3/400 and an Apple G4/450 (AGP) for comparison.
  2. Applications Performance: How the upgrade performed in real world CPU intensive tests like Photoshop 5.5, SoundJam MP, Infini-D, After Effects, Bryce 2, and demanding 3D games.
  3. Software Controls: Ease of use and features of the supplied control software.
  4. Installation: This page has a complete illustrated guide to software and hardware installation. Includes information on the B&W G3 Firmware Updater (removes G4 block). This page was published earlier this month as a guide to ZIF upgrades in the B&W G3. (Note for Beige G3 Owners: You should read this FAQ note on VRM (Voltage Regulator Modules) to make sure they do not have the "Royal" brand VRM which Newer Tech says can damage G4 CPU Upgrades in Beige G3s.)
  5. Specs/Design: Features and details on the hardware design. Includes package contents and compatibility information.
  6. Summary: Final comments, summary and pricing/availability.


The MACh Speed G4z is listed as compatible with the following Mac models:

  • Apple Blue and White (B&W) G3 (tested here)
  • Apple Beige G3
  • Apple All-in-One (AIO)

They also list the G4/400 which I suspect means the Yikes (PCI) systems which use basically the same motherboard as the B&W G3.

When used with their CarrierZIF CPU card, the G4z is compatible with the following older Macs according to their current info:

  • PowerMac 7300-9600
  • Umax J700 and S900
  • PowerTower Pro and PowerWave
  • Genesis MP 720 and Millennium

Note: XLR8's G4z PDF file for system compatibility when used with the CarrierZIF lists the PowerCenter/Pro and PowerTower which are Catalyst based Macs and not G4 compatible to my knowledge. I've notified XLR8 to verify that info. These systems are compatible with the CarrierZIF when used with a G3 CPU module however. The PDF file also notes a free Performance Package, which XLR8 notes is only offered with the G3 and G3z models. These errors should be corrected within a day or so.

B&W G3 Firmware Notes:

As most readers know, the Firmware update 1.02/1.1 prevents a G4 CPU from working in a B&W G3 (proven here back in August, 1999). XLR8 supplies a Firmware Updater that removes the G4 CPU block. See the Illustrated Installation Guide for a walk-through of the software and hardware installation of this upgrade in a B&W G3 and notes on rev 2 B&W G3s that may have shipped with v1.1f1 firmware.

Test System Hardware Summary

  • Apple B&W G3
  • Firmware v1.1f4 (Patched by XLR8's updater)
  • 256MB SDRAM (322 clock dimms)
  • Stock 6GB IDE hard drive (5400 rpm, 512KB cache)
  • 32X CDrom drive
  • ATI Rage128 Orion PCI Video card (in 66MHz PCI Slot)
  • All OS 9 Altivec extensions were enabled for G4 CPU tests
  • OS 9.0, VM off, QT 4.0.3 Pro, QD3D 1.6., OpenGL 1.1.2, [No Libmoto]
  • Apple G4/450 AGP (Sawtooth) Comparison System
  • 256MB SDRAM (222 clock matched dimms)
  • Stock 20GB WD Expert (7200rpm, 2MB cache)
  • OS 9 tests used 18GB WD Expert (7200rpm 2MB cache) slave drive
  • All OS 9 Altivec extensions were enabled
  • OS 9.0, VM off, QT 4.0.3 Pro, QD3D 1.6., OpenGL 1.1.2, [No Libmoto]

You can follow my preferred path through the review by continuing to the next page, or use the links below to jump to a specific page.

Index of XLR8 MACh Speed G4 400MHz Review Pages

Intro | Benchmarks  | Appl. Tests | Software Controls  | Installation | Specs/Design | Summary

- or -

Copyright © Mike, 1999.
All Rights Reserved.
All brand or product names mentioned here are properties of their respective companies.

Users of the web site must read and are bound by the terms and conditions of use.