Originally Posted by Cheimison
64 bit processors compute 64 instructions at a time. Thus a 128 instruction count is processed in two passes, as opposed to 4 with a 32 bit processor. Thus it is 'faster'. This frees up resources, thus more can be spent on graphics processing (which is still done partially by CPU) and map volume information.
I dont think CPUs do that much for texturing... they have more than enough to do with AI, physics and geometry... i dont think the little resources that might be used for texturing could possibly warrent doubling or trippling the texture resolution as shown in those screen shots.
Besides, textures are stored in video memory (usually), if the CPU needed to do anything with them, youd be constantly swapping over the AGP bus to system memory. Im pretty sure it doesnt work that way.