PowerPC vs Intel
Processor Performance Comparisons -BYTEmark

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Below you will find various processor comparisons for PowerPC and Intel based chips. Testing was done using BYTEmark Byte Magazine's standard for measuring raw processor performance and appeared in Byte Magazine.


Below you will find the scores for the individual test that make up the BYTEmark testing suite expressed as the percentage of performance when compared to the G3/300 which receives a score of 100%. For information on these scores please visit the BYTE Magazine web site.


What is the BYTEmark test suite?

The BYTEmark benchmark test suite is used to determine how the processor, its caches and coprocessors influence overall system performance. Its measurements can indicate problems with the processor subsystem and (since the processor is a major influence on overall system performance) give us an idea of how well a given system will perform.

 The BYTEmark test suite is especially valuable since it lets us directly compare computers with different processors and operating systems. The code used in BYTEmark tests simulates some of the real-world operations used by popular office and technical applications.

What do the different test scores in the suite mean?

There are 10 tests in the BYTEmark test suite. Each uses a well-known algorithm to analyze the full spectrum of processor performance in the same way real-world applications do. Some tests concentrate on integer performance; others test floating point capabilities. You can read more about the individual tests and the operations they measure in the BYTEmark documentation. It's available at http://www.byte.com/bmark/bdoc.htm.

Because processors don't always perform the same tasks in the same way, and thus may sometimes give unexpected results on individual tests within a benchmark suite, BYTEmark performs statistical checks to confirm the validity of results.

What is the advantage of benchmark tests test suite?

PC test centers generally measure performance in two ways: by performing controlled tasks with commercially-available applications, and with custom-built programs designed to test a particular facet of the computer system. Application-based benchmarks perform tasks inside commercially available programs. They're extremely useful for determining relative performance within a given platform, and less useful for ranking performance among machines that use different processor architectures.

The BYTEmark suite forces a system to perform carefully chosen operations natively and in isolation, that is, without assistance from an advanced operating system or other system resources such as a fast hard drive or enhanced video subsystem. Application benchmarks may show that a computer system is fast or slow, but the BYTEmark tests can help determine if the change in performance is due to extra memory or a faster processor, for example. In certain cases they can also be used to demonstrate obscure features (and sometimes flaws) in compilers or in microprocessor architectures.

Remember, however, that a computer's overall system performance is a composite of many factors : the processor, the speed at which it and any L2 cache is clocked, the speed of its physical memory, the speed of its hard drive, the speed of its video subsystem and many other features. Vendors make trade-offs when assembling computer systems in order to achieve desired price points for new machines; these can cause two machines using the same microprocessor to report very different results.

Why do the Bitfield test results vary so much between the two processors?

If you'll examine the chart carefully you'll notice that one test, Bitfield, returns very high scores for the G3 when compared to the Pentium II. The reason? The PowerPC compilers used to build these applications can generate code that's significantly different from that of x86 (i.e., Pentium) compilers.

What's the difference between these compilers?

A lot of it has to do with how the compilers generate code for this test. Compilers generate code based on their knowledge of the target processor's architecture. They use this information to produce machine code that implements the algorithm most efficiently.

Do compiler optimizations impact results?

Yes, because they take advantage of the processor architecture. This is exactly what a software developer wants; it helps speed the performance of the application he's creating.

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Internal Links

  • PowerPC Chip performance compared
  • Check out the Links Page for links to sites with more Processor information
  • More Windows vs Mac Comparisons
  • External Links

  • SPEC vs BYTEmark - which is the better, more accurate benchmark program
  • PentiumII vs the G3 / G4 - MaKiDo compares these two chips
  • Motorola - detailed information about the various PowerPC chips
  • BYTE Magazine review of G3 and Pentium II
  • BYTE Magazine review of the G3/266
  • BYTEmark faq