K7 Athlon's actually just used EV6 bus, to the point where motherboards were compatible with each others if you made a connector adaptor and replaced firmware.
I have had very unconfirmed rumour that K8 involved so much of DEC stuff (starting with it's obviously EV7-derived design) that at one point it still had support for VAX floating point...
Always loved Alpha's, their influence cast a long shadow.