Since most older Macs don't have clean ROMs and will have to run with Speculative Processing disabled I decided to use the default settings. Mac you need to install the vendor's G4 software before installing the upgrade card to ensure that speculative access is disabled when first booting from the G4 upgrade. Application and game tests include Photoshop 5.5 with latest Altivec extensions, Lightwave 3D 5.6D, After Effects 3.1, Premiere 4.2.1, Infini-D 4.01 and Unreal 224b7. Benchmarks used were MacBench 5.0 and two memory bandwidth tests. I'll start with real world application tests since they are the most important.
Benchmark results follow farther down the page.
As noted in my more recent PSBench tests, to eliminate scratch disk activity seen even with a 10MB image file and 140MB of RAM allocated to Photoshop 5.5, the ' History' settings were changed from the default 20 to 1, and I unchecked the 'automatically create snapshot' option. All G4 CPU tests had the 4 OS 9 Altivec extensions active as well as the Adobe current release of the Altivec Core and Lighting Effects Filter that were recently updated and publicly released. The ' 2MB Cache Gain ' column notes the performance benefit from the 2MB vs 1MB cache. Tests with different image sizes than the 10MB test sample may show different results. The total time for the 21 filter tests shows much smaller gains than some specific filters since many filters are not Altivec enhanced, including those that took by far the longest times to complete.