All those images are very easily renderable on DX9 class hardware. I doubt very much whether anything that doesn't support at least 64bit colour will even approach the quality shown in them.
But I also doubt if any
of them are real time renders. Some of the methods required to produce such quality images, such a path tracing etc., will still require an enormous number of cpu cycles. I can image the NV3x could render them faster through the use of some pretty advanced shader code but it would still be offline rendering.
Also, IMO, the images (though they look nice) could have been rendered on an R300 just as easily as an NV3x. Just maybe not as quickly, and remember quickly is a relative term here - it may have been tens of minutes.
We need to know some real hardcore stuff about the NV3x architecture, not what it's capable of offline. But what it can do in real time. How wide is the memory bus, 128bits or 256bits, how many cycles get eaten by FSAA or Anisotropic filtering. What improvments have they made to the Z-Occlusion code and how well does the chip utilise the bandwidth available? Thos are the kinds of things I want to know. And I want to know NOW