When people buy a new PC they almost certainly choose one with a dual core, quad core or maybe even more-core processor. Multicore processors first started to appear in about 2006, and the clear implication of these devices is that they will be faster than those sad old single core units. They seem like a logical choice, because surely everyone wants their computer to be really fast, but will multicore really make a difference, or are we wasting our money?
Each core of a multicore processor runs independently, so they only do any work if they get sent some to do. Most people use a very limited range of software like web browsers and office software, and often that software is an older copy they’ve had for some time. This means that for most users it’s fairly unlikely that any of their software will address more than one core, so there’s an immediate risk that one is busy while all the rest sit idle. Games tend to push the capabilities of a PC much further, but even game producers have only recently started to make software that needs multi-core to run, because they only want to sell products that the majority of consumers can use. Some types of software put a much higher load on the processor and the most commonly used on home PCs is video editing software. The latest packages can split up high load tasks and share them across several cores, although again there are a small number of users who both undertake these tasks and have up to date software.
Another thing that will impact the utilisation of each core is the operating system being used. Windows 7 will share the processing load among the cores when more than one programme is running at a time, bringing more of them into play, but none of the earlier versions could do this. So if you use only web and office software, use earlier versions of windows, or only use programmes one at a time then multicores aren’t doing anything for you. This covers a large proportion of users, because using more than programme at a time means they need to be doing something with them all, not just having multiple windows open in the background. For these users, best value is to be found by choosing a processor based on highest clock speed, rather than on number of cores.
In the final assessment many people buy PCs that are capable of far more than they get used for, and multi core processors and just one element of unused capacity.