Despite the fact that Intel's four core Kentsfield processors have been out for a few months now, we're still at the very early stages of the quad core revolution. Supreme Commander will be the first game on the shelves that can make use of four separate CPU cores at once for a performance boost, with Half-Life 2: Episode 2 to follow later in the year.

AMD's marketing department has coined the phrase 'megatasking' to describe running several CPU intensive tasks simultaneously - high def video encoding, gaming and MP3 streaming to an extender, for example. Getting PC owners to actually try running all that stuff on a regular basis, let alone feeling compelled to splash out on hardware that lets them do it, is going to take bit longer than it did to come up with the name, though.

All of which explains why Intel's Core 2 Extreme X6800 still costs system builders the same amount as a QX6700 quad core chip. It's slightly faster in games and single threaded applications, despite only boasting two cores.

Caveat over

If you were to ask us what chip to buy for tomorrow, though, we'd absolutely encourage you to go quad core. It's a technology that will really come into its own in the next few months, as more games appear that support it and Vista takes over from XP with its more efficient handling of multiple CPUs.

In professional applications - for audio, video, photo and 3D editing, for example - multi- threading is already the norm and as we found in our Kenstfield reviews, performance in optimised applications scales very nicely as you add more processors. Which is why we've been looking forward to AMD's response to Core 2 Quad quite keenly.

And here it is. Quad FX. Formerly known as 4x4, it's as different to Intel's solution as it's possible to be. First of all, where Intel's Core 2 chips are a brand new design from the ground up, Quad FX is simply two old-style dual core Athlons plugged into one board.

One of the key strengths of the AMD's 64-bit architecture, that enabled it to compete so effectively against Intel's Xeon server chips, is its ability to talk chip-to-chip and share memory resources across the Hypertransport bus.