Instead of having a bus with a common medium (traces ... use a 1.0 mm pitch (compared to 1.27 mm for PCI), a 1.4 mm spacing between the contact fingers and the same 20° chamfer angle as PCI ...

PCIe superseded PCI and PCI-X. Unlike its PCI predecessor, which used a shared bus, PCI Express is a switched architecture of up to 32 independent, serial lanes (x1-x32) that transfer in parallel.

Here the common 1.6 mm seems to be a good match ... Covering the intricacies of the ISA and PCI bus would however take a whole article by itself. For those of us who have had ISA cards with ...