The Sapphire X600XT VIVO is the other of the two ATi chipped graphics cards in this group, in this case the Radeon X600XT. Although this is a PCI Express chip, the X600 is based on the Radeon 9600, which in turn is based on the Radeon 9500, and that was a cut down version of the very first DirectX 9 chip of all, the Radeon 9700.

That means that the underlying technology dates back to late 2002 which is a lifetime in the world of graphics chips, and although ATi has carried out extensive development of the silicon to make it more efficient, it is definitely showing its age.

In our benchmark tests the Sapphire X600XT was a little slower in 3DMark05 than the Leadtek GeForce 6600, but in Doom 3 it was comprehensively eclipsed, despite the fact that the Sapphire runs its core and memory 200MHz faster than the Leadtek.

As the workload increases the GeForce 6600 looks better and better while the X600XT limps along behind. Allowing for the fact that the Sapphire has a Video-In feature which adds to the value of the card, the Leadtek and Sapphire pretty much cost the same, and that doesn't make this card very desirable.

When it comes to overclocking, Sapphire includes a copy of the Redline utility in the box. It's a cumbersome piece of software that is less user-friendly than Nvidia's Coolbits, and we would far rather see an overclocking utility that was built into the ATi drivers.

The X600XT didn't tolerate much overclocking, which is only to be expected as the chip has already been pushed hard by ATi over the last two years. The improvement of some 15 percent was welcome but we were starting from quite a low point so the overclocking couldn't transform the card, and it looked rather lame compared to the GeForce 6600 which overclocked by about 30 percent.

In short, the Leadtek GeForce 6600 costs the same as the X600XT, it performs better out of the box, and it also returns better results when you overclock it.

Sapphire has done its best to fight against the limitations of the X600XT chip and it includes a software package of Cyberlink PowerDVD for DVD playback and PowerDirector for video editing, but nothing can change the fact that its performance is similar to the XFX GeForce 6200, and that makes the Sapphire X600XT VIVO too expensive.