ATI looks to be teeing up its latest batch of graphics chips so here's a little glimpse of what the new-look Radeons promise to deliver. Enter the X1800 XL, which opens the door to an entirely new ATI architecture.

Most of the new technology revolves around increasing efficiency. For example, the way memory is used has been comprehensively rejigged. In ATI's new design, the memory controller receives a lot of support from the rest of the card, thus allowing it to keep everything flowing more smoothly. The Z-buffer (which stops the card from drawing unnecessary pixels) has been optimised - ATI reckons the system catches 50 to 60 percent more than before - and pixel shaders are more carefully handled as well.

So with these improvements, plus the Avivo functions for boosting video and display output, you've got a pretty irresistible package, right? Well, we wouldn't exactly go that far.

The new architecture may be extremely efficient, but this didn't really show up in our tests. Visually it was pretty much on a par with its biggest rival, the GeForce 7800 GT, but only in Splinter Cell did it produce any real performance advantage - and that was rarely more than 3fps (frames per second). It moved ahead on Half-Life 2 by little more than a frame, and fell behind in both Far Cry and Doom3 - dramatically, in the case of the latter. The X1800 tended to fare less well as you stacked up the detail settings.

The X1800 XL has some very nice features and the drivers have a level of programmability that mean its performance could improve markedly in coming months. In the meantime, though, it is difficult for us to recommend.