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Suraj R.
Jul 9, 2013, 01:24 AM
I got the 2013 13" i5/8/128 MBA and I'm completely satisfied with the performance. Since the base clock speed is 1.3 GHz and the max is 2.6 GHz, I can essentially think of my machine to be a 2.6 GHz without Turbo Boost (right). And with hyper threading my machine reads my two cores as four (in Activity Monitor I can visually see the workload on each of the four threads), or quad core.

So then isn't my machine a 2.6 GHz Quad Core i5 without hyper threading and turbo boost?



keatre
Jul 9, 2013, 02:46 AM
Since the base clock speed is 1.3 GHz and the max is 2.6 GHz, I can essentially think of my machine to be a 2.6 GHz without Turbo Boost (right). And with hyper threading my machine reads my two cores as four (in Activity Monitor I can visually see the workload on each of the four threads), or quad core.

So then isn't my machine a 2.6 GHz Quad Core i5 without hyper threading and turbo boost?

I think you're mixing up terms a bit here... Short answer to your question is No.

If you were to turn hyperthreading and turbo boost off, you would have a 2 thread 1.3 Ghz processor. You can only achieve 2.6 Ghz with Intel TurboBoost. You can only have 4 threads run simultaneously with Intel Hyper-Threading on.

Now, don't let this dissuade anyone. Apples to Apples comparison between previous generations of architectures is not equivalent. All the things equal, Ivy vs Haswell - Haswell will perform calculations faster.

I hope this answers some of your questions.

Suraj R.
Jul 9, 2013, 02:01 PM
I think you're mixing up terms a bit here... Short answer to your question is No.

If you were to turn hyperthreading and turbo boost off, you would have a 2 thread 1.3 Ghz processor. You can only achieve 2.6 Ghz with Intel TurboBoost. You can only have 4 threads run simultaneously with Intel Hyper-Threading on.

Now, don't let this dissuade anyone. Apples to Apples comparison between previous generations of architectures is not equivalent. All the things equal, Ivy vs Haswell - Haswell will perform calculations faster.

I hope this answers some of your questions.

I think you misread my final question (I didn't word it great).

I meant to say, isn't my machine's processor THE SAME AS another processor clocked as a 2.6 GHz Quad Core i5 that doesn't have hyperthreading and turbo boost?

I'm asking if its the same as a 2.6 GHz Quad Core i5 that doesn't have either of these features at all.

jdechko
Jul 9, 2013, 02:10 PM
No.

The 1.3 i5 is capable of hyperthreading and Turboboost, yes. But it can only hit 2.6 GHz with 2 cores enabled. If I remember correctly, it can hit about 2.9 with only one core. But it can't hit the 2.6 running all 4 cores simultaneously.

So in theory, the Haswell i5 in the Air is going to give you about as much performance as a dual core 2.6 processor. But again, it's complicated.

cake1
Jul 9, 2013, 04:02 PM
Hi,
I think you are confusing some stuff and you are worrying for no reason.

Firstly, you cannot assume the frequency of the chip to be equivalent to "horse power". Yes, increasing the frequency you are getting more done per second and generally you get a performance boost.

However with each generation cpus also do more per clock cycle. Additionally, newer chips generally have a whole bunch of new technology improving power efficiency, memory controllers etc.

If this makes you feel better you can say that the chip in your cpu is faster then some of the older generation CPUs at 2.6 ghz. But the main point is that its more power efficient. Insanely power efficient I would say. If you are interested in knowing about how your hardware works, by any means, go ahead and read on the subject. Otherwise, if you are not really interested, you might as well abstract yourself from this "CPU speed " matter. As you said, it is fast enough for your needs - it doesnt matter if it runs on a low frequency as long as it does it job (:

I have the same cpu in my MBA and i love it for how cold end efficient it is (: