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Comment by UnoriginalGuy | Hacker News Reader

While I agree that 16x800 Mhz is more accurate than 13 Ghz; I wouldn't say they got the terminology "wrong."

A lot of companies are using the combined totals to tell how fast/big/etc something is. It isn't even a recent development either.

Just for one example, if you go to Dell's store right now you'll find computers with 8 GB of RAM; but what they fail to tell you is that that is 2x4 GB sticks rather than 1x8 GB stick. So it is actually the "total" RAM in the machine.

Now you might argue that for technical reasons there is a difference between how RAM and CPU-cores are exposed to the underlying software, but that within its self is only true in some infrastructural designs, but not true in others (e.g. Sometimes two cores pretend to be one, sometimes a single core pretends to be two).

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The RAM example is terrible. Accumulating RAM is application-transparent. Processor accumulation is not.

Two small shovels aren't the same as one big shovel, but two small bags of dirt are basically the same as one big bag of dirt. If you're going to continue with the memory analogy, this would be like combining the graphics memory and general purpose RAM into a single figure.

So a better analogy would be to quote total FLOPS.

It would've been better to call it a hexa-core 800mHz machine.

Isn't hexa-core six cores? Whereas this has sixteen.

Yes, probably it should be a hexadecicore or something along those lines.

I take pause at the term of "hexadecicore" and as we go up, it just starts to get more complicated... what would you call a 32 core machine? That just seems like an overly complicated and confusing approach to the problem.

Well, I was obviously playing on "hexadecimal" which isn't great itself; it's a mish-mash of Latin and Greek, and should probably be "deca" instead of "deci" anyway. Regardless, it can't be worse than those stupid resolution acronyms like WUQXVGA which are, for some inexplicable reason, still managing to survive.

That not really the same though. Hz is a scale of the frequency of a CPU core. So it's not even a gauge of the execution speed of a CPU. You can't really multiply the cores together as the frequency hasn't increased, you've only increased the parallel capabilities (case in point, multi-core CPUs are rated per core, not cumulatively).

RAM, however, can be added together as data can be cached across one or more sticks. Thus adding another stick of RAM does increase the overall total amount of RAM available.

I'm not an expert on this, but I believe this is why clusters are measured in calculations per second (eg FLOPS) rather than frequencies. Calculations run in parallel (such as clusters do) are increasing the overall number of calculations performed per second. Where as multiple cores running in parallel don't increase the clock frequency.

Think of it this way. If I have 1 2-gallon bucket or 2 1-gallon buckets (or 4 half-gallon buckets), I still have 2 gallons of carrying capacity.

But if I watch 1 clock for 60 seconds, the amount of time that has passed is exactly the same as if I watch 2 clocks for 60 seconds or 100 clocks for 60 seconds.

Kind of off topic but is there any major performance difference between 8x1 and 2x4 RAMs?

There can be. In particular in some scenarios the 2x4 GB set might be faster, here is why: http://en.wikipedia.org/wiki/Multi-channel_memory_architectu...

All desktop CPUs have 2 64 bit channels right now, you should never configure a machine with a single DIMM. The bigger server CPUs (e.g. the LGA2011 socket) have four. Mobile SoCs almost all use 1x32, though a few recent high end ones (Intel Medfield and the A6 at least) have 2x32.

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