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More on BTX Motherboards
venger writes "Anandtech has an article on the new standard of cases and motherboards that is soon to be released. Looks like they are trying to cater for the increase in heat devices are now producing while keeping the noise levels down!" We mentioned BTX earlier.
I think I can safely assume that PCI Express has a bandwith that is much faster than that of AGP can ever have
The AGP 8x spec has a max bandwidth of 2.1GB/s, while PCI Express x16 has a bandwidth of 8 GB/s. It might be theoretically possible to create a AGP 32x spec (although I doubt it), but the obvious question would be why?
. But isn't the point of AGP that it allows you to set an arperture and use some of the system RAM as an extension of the memory on the graphics card?
No, the point of AGP was to give a single slot increased bandwidth that's needed for modern graphics cards. PCI just isn't fast enough. Intel wrote into the spec that you could get away with sharing main memory as video memory in order to reduce system costs, but in practice nobody does this except for the absolute bottom tier PCs. The performance hit is huge.
wont AGP still be better?
No. Although it's questionable that PCI-X will really provide any speed increases. AGP 8x has a negligible speed improvement over AGP 2x, and quadrupling the bandwidth again isn't likely to do much either. I'm pretty sure PCI-X can still do the main memory-as-video memory trick, but there's really no need or desire to do so. If your card doesn't have enough memory to hold the textures then you're going to have a massive speed hit when you need to get them from memory. In practice this speed hit is so severe that the amount of bandwidth has relatively little impact on things -- it's the latency that kills.