Mac Color Classic with Presto

The Color Classic uses a 16 MHz 68030 CPU, but the Presto accelerator provides either a 25 MHz 68040 or a 68LC040 (a 68040 without a math section).

The 68040 is faster than the 68030 due to larger data caches (dual 4096 byte caches vs. dual 256 byte caches), runs internally at twice bus speed, and, in the full 68040, has math functions integrated into the CPU instead of on a separate 68882 math coprocessor.

The Sonnet Presto works in the Macintosh LC, LC II, Color Classic, and their Performa twins.

Remember that benchmarks are arbitrary. They measure certain types of performance that may or may not reflect the way you work.

This computer was also tested without the Sonnet Presto accelerator.

Speedometer 4.02

The system was first tested on 26 February 1999 under System 7.5.5 using the internal monitor in "thousands of colors" mode and with a 16 MHz 68882 math coprocessor installed. Results are relative to a Quadra 605, which rates 1.0. Numbers rounded off to two decimal places.

The first set of numbers compares performance at different cache settings without the accelerator.

cache  video   CPU  graphics  disk   math
 32KB  16-bit   0.25   0.23    0.86   1.94
 64KB  16-bit   0.25   0.23    0.89   1.94
128KB  16-bit   0.25   0.23    0.90   1.92
256KB  16-bit   0.25   0.22    0.75   1.93

The second set of numbers shows performance with the 25 MHz Sonnet Presto accelerator using the 68LC040, which lacks the math coprocessor. The only other difference is that the addtional VRAM and the math coprocessor were removed, so these tests were run in 8-bit mode.

cache  video   CPU  graphics  disk   math
 32KB   8-bit   0.82   0.47    0.89   4.19
 64KB   8-bit   0.82   0.47    0.88   4.19
128KB   8-bit   0.82   0.47    0.89   4.17
256KB   8-bit   0.82   0.47    0.85   4.18

Overall, CPU performance is almost 3.3 times faster, graphics performance is doubled, and, despite the handicap of no math coprocessor on the Presto, even math performance is more than doubled.

Because the CPU has very little to do with the hard drive, there is no significant change except at the 256 KB cache setting. At that setting, the Presto shows the same unexpected decline in disk performance, but to a lesser extent than with the original 68030 CPU.

Speedometer 4 was not tested at different video settings.