I was actually just looking at something recently. Intel is selling gigE cards using 64bit 133mhz "pci-x" bus connections. They claim the bus speed at 8Gbps. There's a pdf on them at http://www.intel.com/network/connectivity/resources/doc_library/data_sheets/ gigabit_over_copper_adapters.pdf.
I was looking at this because the latest Dells (PowerEdge 1650) have dual integrated GigE ports, using this chipset. Not that I actually have one or can make any statements about the validity of the above, but if true, getting a gigabit router/firewall for under $2k is just cool. I'd love to have a few of these to do some actual throughput tests... (and then, once bandwidth is eliminated as a bottleneck, see how fast a pair of gigahertz+ processors can do AES ipsec...) BTW, I think your calculations are a few orders of magnitude off. If I can only transfer 500bps across the bus, my modem will severely overload my pc. :) Perhaps you meant 500 Mbits/sec. -Joe > However, 100 megabytes per second ? I think that's beyond the > standard PCI > bus capability... > > 32bit bus running at 33MHz = approx 1000 bits per second, however > there are > (at least) two network cards; you have to read the bits from one > and write > them to the other, so this gives a max throughput of 500 bits per second > (assuming the processor can keep the PCI bus saturated, and the > NICs can keep > up with efficient reads/writes). > > This is one reason I've never quite understood the existence of Gigabit > Ethernet cards with standard PCI interfaces..... they're hardly > going to work > efficiently.
