AMD has taken a bold step with the latest version of the Athlon 64, as the new FX-60 has a clock speed that is 200MHz slower than the previous FX-57. At first glance this seems like lunacy but the big news is that FX-60 is a dual core processor so it has two cores humming away at 2.6GHz, and that gives it an enormous amount of processing power.

Each core has 1MB of L2 cache and the layout of Athlon 64 with its Hyper Transport interconnects and integrated memory controller means that the two cores can communicate with each other in a way that Intel can only dream about.

The new FX-60 has a great deal in common with the dual core Athlon 64 X2 4800+, which has a core speed of 2.4GHz, so in most respects you can think of the FX-60 as an X2 5000+.

The processor uses Socket 939 and AMD has worked wonders to keep the power requirement and thermal output of FX-60 very close to the level of FX-57, despite the fact that it is doing nearly twice the work. This means that any decent Athlon 64 motherboard should support FX-60, although it will probably require a BIOS update.

Get the latest Dell Coupons and other computer coupons at CheapStingyBargains.com.

Of course FX-60 has one important extra feature; the unlocked clock multiplier, which allows the overclocking fraternity to do their utmost to squeeze some extra speed from their new processor.

The FX series is aimed at the gamer who wants - or needs - the ultimate in performance, and this is where things get a bit messy. The FX-60 has a slower clock speed than the FX-57 so it can only pull out an advantage if it is running multi-threaded software that can take advantage of both cores.

The only game that we know of which definitely supports multi-threading is Quake 4, so if your PC is CPU limited (i.e. you have a high-end graphics set-up and you plug in an FX-60) then you will see a significant advantage. With the vast majority of games that is not the case unless you are running an FX-55 or slower, in which case the FX-60 has more clock speed and also an extra core. See the table below for a comparison of the FX-57 with the FX-60.

Of course, gamers shouldn't really be running applications in the background while they are playing if they want top performance. The rest of us will see an immediate benefit from a move to a dual core processor as we run an e-mail agent, a word processor, anti-virus, a browser and loads of other gubbins too. As time passes it is inevitable that more software and games will be written to take advantage of multi-threading and multi-core processors.

You may not be surprised to learn that FX-60 comes at a hefty price, and even though it has the same list price as FX-57 (which retails for £730) we have found FX-60 on sale for £820. That's a monumental amount of money, but FX has always been expensive and there is no doubt that FX-60 is the best processor that AMD has ever produced. But only you and your bank manager know if you can afford it.

AMD has moved its premium Athlon 64 FX to dual core and the result is stunning. In our testing the FX-60 made FX-57 look positively slow and it also had a significant edge over the X2 4800+. Although FX-60 is a product that is aimed at gamers it is the PC user in the street who will really appreciate the multi-threaded speed of the new processor. However, we doubt that he or she will wish to pay the asking price.