Comparing the "Intel iMac" to the PowerPC: Photoshop Works at Approximately a 70% Rate Compared to the iMac G5

Jan 18, 2006

We recently acquired Apple Computer, Inc.'s new iMac (17-inch model) featuring an x86 microprocessor that was released on January 11. Before tearing it down, we set it up and first tried the computer. The microprocessor used in the computer is the 1.83 GHz "Intel Core Duo."

Our tear-down team attempted to measure the Intel Mac's performance compared to the PowerPC benchmarks when using the "Adobe Photoshop 7.0" software. We used part of the filtering processes specified in the "HI-FI-Ultimate-Bench-PS7" distributed by HI-FI ( This benchmark test is designed to measure the performance of 37 filtering processes, but we only measured the first 10 processes, not having enough time to conduct the whole test. We compared the new computer with an iMac G5 owned by the Tech-On! editorial office. It is an older computer featuring the 1.6 GHz PowerPC G5 microprocessor. However, its memory storage capacity of 768 MB is larger than the Intel iMac's 512 MB.

Despite some variances depending on the kind of filters, the obsolete iMac G5's results were largely faster than the latest computer. Based on a total time needed for the 10 filtering processes, the Intel iMac works at about 73% of the speed rate compared to the old product. In other words, as long as Photoshop is used, the current product works faster. This proved that the Intel iMac is truly "a sufficient model for most people," a description Apple's CEO Jobs used in his keynote speech at Macworld Expo 2006, San Francisco, where the computer was unveiled for the first time.

When running current PowerPC software, the Intel iMac uses an OS-embedded binary translator called "Rosetta." Rosetta converts object codes for PowerPC into x86 microprocessor codes. Therefore, software for PowerPC processors, including the current Photoshop, must work at a slower rate reflecting the program conversion carried out alongside. Taking into consideration that the PC uses converter software before processing, 73% compared to the old model may be regarded as a fair rate.

Takeyoshi Yamada, Nikkei Electronics