Originally written December 2009

What is a “core”?

Does it mean the computer’s made by Apple; hence ‘Apple core’?

No, but that’s a humorous idea nevertheless, even if slightly esoteric: -

A ‘core’ is a separate processor; therefore a single-cored processor is a single processor. A dual-cored processor is 2 processors in the same chip, and so on…

A processor is a vital part of the computer; it’s where the main calculations are carried out; the computer’s brain, if you like. You may often have heard it said that two heads are better than one, and 2 heads = 2 brains, 2 processors, 2 cores.

A processor core is not a computer in itself, though, any more than a brain is a human-being. As the human body requires many different organs to make it run properly and continue working; such as a nervous system, blood vessels, heart, – so in the same way a computer requires many different parts to keep it working; such as data buses, power rails, chipset.

At the time of writing, the number of cores generally available are: -

1 core. (Intel Atom (32-bit low-power processor currently used in many netbooks.))

2 cores. (AMD and Intel – various.)

3 cores. (AMD Phenom.(AMD’s previous generation of processors, mainly using 65nm fabrication.))

4 cores. (AMD and Intel – various.)

I believe that 6, 8, and maybe even 12-cored-offerings may be on the horizon or indeed currently in prototype from both AMD and Intel also.

What’s the advantage of having all these cores?

That depends on what software you’re running at the time, and what that software’s doing: -

Very basically; a single core can only perform 1 calculation at any given point in time. It works so fast that it may appear to be doing more than 1 thing at once; but even if it’s running 2 or more processes simultaneously, it’s only doing one calculation at a time: Therefore it’s doing a calculation for process A, and then it’s doing a calculation for process B, and then back to process A, and so on… ‘Introduce 2 cores, though, and core 1 can do all the calculations for process A, while at the same time core 2 can do all the calculations for process B; at least in theory. In practice it’s a little bit more complicated than that, though. – But that’s beyond the scope of this article.

Let’s not, at this point, forget hyperthreading: Hyperthreading is a technique introduced by Intel, ( -and later developed and adopted by AMD) in the very-early 21st Century, that makes each core of the processor appear to the operating system as 2 cores. This doesn’t mean that each core is as fast as 2 cores, or as effective, but each single core with hyperthreading will still be faster than a single core without hyperthreading.

If the program that you’re running is CPU-intensive; then it’ll benefit from running on a multi-cored processor by being able to utilise the processing-power of an entire core all to itself; whereas if it were run on a single-cored processor, it would slow the execution of other programs down, and they would likewise slow it down too.

But there are programs; particularly games, that are written in such a way that they utilise the processing power of more than one core in their execution. In fact, lately, entire operating systems are written to take advantage, in part at least, of the processing power of more than 1 core; such as Windows 7, for example. Writing such software can be rather complex and tedious; which is part of the reason why every single program in existence these days doesn’t take advantage of all the cores of a multi-cored processor.

Great; so what are you recommending?

Personally I recommend a dual-core or more processor; depending upon what software you’ll be running. – In fact, unless you’re talking about a netbook made in 2009 or earlier, or a laptop made before 2008, you’ll be fairly hard-pushed to find anything still working that has a single-core processor fitted. – Maybe a 6-year-or-more-old desktop?

If you’re a gamer, or you use CAD software; both of which are extremely processor-intensive and designed to use more than 1 processor-core, then the more cores the better. – Also the more RAM the better too; which is where running a 64-bit operating system comes into its own.

If you’re a standard run-of-the-mill computer-user, then you should currently happily breeze through with a dual-core processor.

If you run Windows 7 64-bit, or a 64-bit Linux operating system, then I suggest doing so on a processor with 3 or more cores for optimum performance, although 2 cores will do the job fine also.

Mac users: Well Apple seem to be fairly proficient at ensuring that their latest computer products are good enough for anything that the users throw at them; so I’ll leave Macs out of the equation.

Is there anything you’d like to add to the above, or is there anything that you feel I missed? If so then please leave a comment.