First of all AGP (acel graphics port) uses the ram or memory to store textures and 3d information. The agp is supposed to be at least 4x faster than the pci graphics display however these improvements have not been all that noticeable as yet.
Anyhow the agp is suposed to support the transfer of 520 mb/s of data with the agp 4x being able to do 1 gig p/s , but this is only when the mobo's support it. And of course this means better image quality through larger use of textures more life like graphics and special effects etc.
The fact is computers are ever evolving they are always in a constnt state of change so you will always find yourself buying a system or parts then 3 months later drooling over something else.
I think by the term do more you mean more complex ? Things will get better just wait and see the implementation of the T bufer from 3dfx and the NV10, AGP 4x, Camio chipset, Athlon, RAMbus ram etc.
The new video cards will be so NON cpu dependant so your cpu will be able to concentrate on things like AI , Your best bet is to wait a while so that all or most is revealed so that you can make a clear judgement as to what suits your needs.
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