But even we Mac faithful need convincing. While the stability and power of Mac OS X has never been in doubt (I am yet to crash the pre-beta developer preview), speed is always a concern. That is why I was disappointed to see the benchmarks comparing the G3 with the G4, using Electric Image 2.9.2. EI has no optimizations for the G4's SIMD Altivec extensions, so it's basically running equivalent to a 500mhz G3 500 that is at least a year old. I have recently upgraded to a dual 500mhz G4, and while few Mac OS 9 applications are updated for both Altivec and symmetric multiprocessing, the ones that are have shown dramatic speed improvements.
I have done two tests for my own reference to compare the speed improvements:
Photoshop 5.5's lighting effects filter on a 29mb RGB EPS file:
- 5 lights down filter; dual G4 500 with MP and Altivec extensions disabled: 29.1 seconds
- 5 lights down filter; dual G4 500 with MP and Altivec extensions on: 5.2 seconds
Soundjam MP 2.1 MP3 compression: 3 min., 21 sec. AIF file from hard disk
- iMac DV G3 400: 58 seconds
- dual G4 500 with MP and Altivec extensions on: 18 seconds
While these aren't 3D renders, they do show that math-intensive computations are significantly accelerated by both the dual processor and the G4's Altivec extensions.
I'm hoping that when Maya 3 for Mac OS X is released, you'll take another look at the G4 running on the Unix-based OS X, so that the value of both Mac SMP and Altivec can be gauged accurately. Maybe you could try it with NewTek's LightWave, which is supposed to have an OS X and G4 optimized version coming out.
Dave GirardArt Director, Vice Magazine
At the time we ran our feature on the Macintosh, neither OS X nor dual-processor G4s were available to us. In any case, we do try to run tests and reviews on equipment that is post-beta and available to the world at large. Thanks very much for sharing your preliminary tests with us. You're right that much about G4 3D performance has yet to be revealed, and will become clearer as OS X and new high-end 3D Mac OS applications ship. We look forward to reviewing Maya for the Mac and the other ports that are sure to follow. Look for our coverage of them.
Your article on the G4 in the July issue revealed a significant fact: The three speed comparisons show the G4, with 1.89 times the CPU rating of the G3 notebook, is only 2.22 to 2.32 times quicker in the Photoshop file manipulations than the G3, and exactly 1.89 times quicker at rendering the test image. And this with the advantage of a 7200-rpm hard drive in the G4 (versus a super-slow 4200 to 5400 rpm hard drive in the G3) and a superior graphics card. So much for the 'supercomputer' architecture of the G4 chip. The real story regarding the G4 is Apple's incredibly effective misinformation campaign behind the incredibly mundane G4 processor. Now that would have been an interesting article! Otherwise, covering yet another over-hyped Apple product in a magazine devoted to workstation-class hardware is a bit off topic.
Randy GoertzenWebWorks Internet
Calgary, Alberta, CanadaAs Dave Girard comments in the previous letter, applications that capitalize on the G4's 3D performance are in short supply. However, that situation is changing as developers from Alias|Wavefront to Gestel begin to port their applications to the Mac. We think the commitment of vendors such as these says a great deal about the viability of the platform for 3D.
We welcome any insights you have to offer that would further our readers' understanding of topics discussed in this issue, or that concern the computer graphics industry in general. We may edit your comments to conform to our style and space requirements.
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