Tuning Cool'n'Quiet: Maximize Power And Performance, Part 2

Benchmark Results: Cinebench R10

Unlike the other benchmarks in this article, Cinebench R10 is unique because it stresses the system and processor with different scenarios. There's the OpenGL viewport test, which measures graphics card performance, the single-threaded render test, and the multi-threaded render test, which measures processor performance.

That first part of the graph seems familiar doesn't it? As with SuperPi, performance in Cinebench's OpenGL and single-threaded test suffers when you enable Cool'n'Quiet on the Athlon X2 and Athlon II. In the multi-threaded render test, all cores are utilized--no more thread “jumps.”

Let's look at the test results. Since we’re more interested in processor performance, we're going to focus on the single- and multi-threaded render test results.

We noted before how asynchronous clock changes were adversely affecting performance in single-threaded applications. Cinebench's single-threaded rendering test confirms this. As in SuperPi, “fixing” this behavior returns performance to where it should be--very close to levels without power management. Admittedly, it's still lower, but the difference is small enough not to be noticeable in real usage situations (1–3%); they may even be normal variations between test runs.

The lack of L3 cache and asynchronous clock changes seems to adversely affect performance more on the Athlon II X2 250. It’s more pronounced than on the Athlon X2s. But once that’s not a factor, everything falls into place, and the Athlon II X2 250 takes the lead among dual-core processors due to its higher clock rate. Not surprisingly, the Phenom II X4 955’s 3.4 GHz clock also allows it to take the top position.

The multi-threaded rendering test is basically similar to what we’ve seen before in 3DMark Vantage.

It might be surprising to some, but the results we see here are what we expected when we saw the earlier SuperPi and WinRAR results. Yes, average consumption-wise, the greater number of cores a processor has (and the higher its clock rate), the higher its power consumption. This is true for both single- (SuperPi) and multi-threaded (WinRAR) applications. But both test results also show that if you can get operating voltage low enough, the power consumption differences shrink significantly between a quad-, triple-, and dual-core processor.

With SuperPI, which is purely single-threaded, total power consumption still favors a processor with the least number of cores. In WinRAR, it’s the reverse. These Cinebench results confirms this, and add a new twist. Even with long periods of single-threaded work (on the OpenGL and single-threaded rendering test), once you run multiple threads (and quite possibly, multiple applications), the quad-core processor actually consume less power. There is catch: you need to reduce the operating voltages.

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  • Anonymous
    I would have liked to see how the quad 810 processor would have gone, considering it is just one peg above the triple core 720, and a few pegs below the 945 and 955 - perhaps it yields a nice balance/performance/voltage ratio? Certainly interesting given that it is a 95w processor, but possessing four cores, I guess that it would have trumped the 720. Maybe AMD sponsors these articles, and have to sell a few more 720s first.
  • chispas
    AMD 810 FTW
  • silverblue
    I doubt AMD sponsors these. Have you seen how poorly the 710 does at DivX? I doubt that DivX will change their code for triple core CPUs, so the 720 will behave similarly to the 710. In addition, this guide is an AMD-only guide.