Turbo Booster – Can It Damage CPU?

So, I ran some Cinebench R11.5 benchmarks to get more information about the single threaded performance of my i5-3427U¹ (1.8-2.8 GHz) CPU:

1 thread → 1.10

I also contacted the author of the linked article by AnandTech - @anandshimpi². Anand Lal Shimpi was so kind to send me a benchark chart which compared the single threaded performance of the 2011 13" Macbook Airs with the 2012 13" Macbook Airs using Cinebench R11.5.

Into this picture, I have added information about the maximum single threaded CPU clocks along with a comparison of the measured performance such as Anand Lal Shimpi has suggested.

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In this info graphic I am comparing specifically:

• 2011 13" Macbook Air, i5-2557M 1.7GHz/2.4GHz/2.7GHz
• 2012 13" Macbook Air, i5-3427U 1.8GHz/2.6GHz/2.8GHz

As you can see, the single threaded clock of the 2012 model is 3.7% increased in turbo boost mode.

However, the benchmark score saw a 9.9% increase which is not simply due to the higher clock, but also due to the more efficient Ivy Bridge architecture which is about 5-15% faster³ than Sandy Bridge.

In sum, the benchmark scores are as expected whereas the Turbo Ratios log entries are not. Anand Lal Shimpi had "figured it was a bug, submitted it to Apple back in July"⁴.

There may be a way to view your CPU's clock speed at this exact second, but as mentioned elsewhere, it is a constantly changing variable (due to Turbo Charge). Comparing clock speeds between different CPU generations, especially nearly five years apart, is also not at all useful.

A much more useful approach would be to use benchmarks. MacWorld uses Speedmark 8 to test most (if not all) Mac models that are produced, and there is a list here of the results. They "take the performance results from the 15 individual tests that make up Speedmark and boil them down to a single number", resulting in an easily-compared list which reviews multiple facets of the computer (not just the CPU). That list does not yet have the new MacBook models on it, but it likely will soon.

You can also compare scores on the GeekBench browser, which directly measure the CPU's performance. Your model's benchmarks are here and average about 1950. The Core M-5Y70 processor, which powers the new MacBook, is available at 1.1 GHz, 1.2 GHz, or 1.3 GHz. The only benchmarks currently available are for the 1.3 GHz version of the CPU, and the score for that averages about two times higher than your model's score. (Hence why the clock speed is irrelevant when comparing different generations of CPUs.)

A score of two times higher on GeekBench indicates two times the performance. Even accounting for the slower base models at 1.1 GHz and 1.2 GHz, performance will still be significantly increased versus your existing MacBook Air.