As technology marches on and the transistor count of CPUs and GPUs alike continues to rise, there is a natural push for ever smaller transistors. The reduction in size brings with it less power consumption, which in turn means the chips don't run as hot, and, because they produce smaller chips, more of them can fit onto each silicon wafer, reducing the relative manufacturing cost of each chip and theoretically giving us lower high street prices for our hardware. However, changing manufacturing processes can be a high risk business, which is why convention has it that manufacturers will release brand new architectures on existing tried and tested processes, as was the case with the 8800 GTX and HD 2900 XT. As the architecture then matures, with the introduction of lower powered mid-range parts and later refresh parts, the newer manufacturing process can be introduced.
It's this path that the 8800 line has followed with the G80 core at the heart of the 8800 GTX and GTS being made using a 90nm process and the 8800 GT being powered by the G92 core that's made using the newer 65nm process. Now the change may not seem like much but it actually equates to a 34 per cent reduction in size for any given chip design, or conversely a 34 per cent increase in space to manufacturer more chips on each wafer. The upshot of which is smaller, cheaper, less power hungry chips, and that can only be a good thing. However, the G92 isn't just a die shrink, there's a little more to it than that.
For a start, the video processing engine, dubbed VP2, that was featured on the 8600 range, has now found its way into the 8800 GT. So you can enjoy high-definition video without your system grinding to a halt. The final display engine that was controlled by a separate chip on the 8800 GTX is also now incorporated into G92. The result is a chip that actually has 73M more transistors than the 8800 GTX (754M vs. 681M) yet still has fewer stream processors, texture processing power, and ROPs than its more powerful brother.
A new version of nVidia's transparency multisampling anti-aliasing algorithm has also been added to the 8800 GT's arsenal, which should greatly improve image quality using this mode, while also maintaining great performance. Apart from this, though, there is little in the way of new graphics features with the new processor.
nVidia has evidently thought long and hard about exactly what areas of the previous 8800 cards were being under utilised and could be scaled back, along with which were more important to maintain. The result is a GPU design that sits somewhere between the 8800 GTX and 8800 GTS in terms of performance but with the features of the 8600 GTS thrown in. To all intents and purposes, this makes the 8800 GTS completely redundant, and the Radeon HD 2900 XT isn't in that great a position either (we'll just have to wait and see whether ATI's upcoming 3850 and 2870 can change that situation though). Moreover, the 8800 GTX and Ultra should still offer more performance but have fewer features, cost significantly more and are more power hungry. The 8800 GT really is building a strong case for itself.