CPU Reviews

The consumer market for processors is very clearly under the spell of a duopoly, with the big two—AMD and Intel—dominating the market. Intel has cornered around 75% of the market for PC processors and now makes all of Apple's CPUs too. But no matter how much market share one or the other has, neither is necessarily 'good' or 'bad' by default. And with both manufacturers constantly updating their ranges, at any given time, both will offer a wide selection of processors that balance price, performance and energy efficiency in various ways.

How many cores?

Most of the processors available today are 'multi-core', which means that they essentially have more than one processor on a single chip. The idea is simple enough as, in theory at least, putting two separate processors next to each other to work in parallel should mean that a computer can complete a given task twice as quickly.

However, for this to work, the software you're using—whether for productivity or gaming—must be written to take advantage of the additional processors. Some software, like Photoshop or video editing software, for instance, is specially adapted to use the extra processing power that's available. When using such programs, performance should improve according to how many cores there are—in other words, a dual-core processor really will be twice as fast as a single processor and a quad-core processor four times as fast. Other software isn't always configured in the same way, however, and although some 3D games can handle two cores, they rarely manage to support four.

How fast?

For a long time, a processor's clock speed was the only thing worth paying attention to when picking a CPU, but things are a little more complicated these days.  To take one example example, Intel currently offers six different 2.66 GHz chips, and with good reason, as they all perform differently. Some have extra cache, some use less power and others feature dedicated extensions and extra instructions that allow them to get more done at the same speed.

These variations can change things so much that it's perfectly possible that a 2.83 GHz processor released in the past few months actually works faster than a slightly older 3 GHz chip. It's best to consider the speed in GHz of a processor as a way of distinguishing models within the same product family, as comparing chips that run at the 'same' speed is not always easy.  That said, an increase in frequency is always an advantage, whatever application you're using.

See Also

> Processors: Performance Index

> Processors: Test Equipment

> Archive: Processors 2008-09