Originally Posted by Liranan
The good old days of total compatibility, how I miss them. Ever since IBM ceased to be the big name in PC's Intel stopped playing nice and refused to cooperate with AMD on these things.
What happened is that the K6-2 was so good relative to the Intel alternatives that when it came time for AMD to renew its x86 license, Intel played hardball and refused to license Intel socket/slot infrastructure to AMD anymore. The K6-series had made it possible for people to keep their old Pentium MMX boards and get Pentium II-class performance via a simple drop-in replacement, or at most, an adapter from PowerLeap or Computernerd.
That was how AMD made a lot of its money up to that point. The best all-around chips you could buy for 386, 486, and 586 sockets all came from AMD. They waited for Intel to abandon a platform, then made better options for it, better than the entry-level solutions from Intel's next-gen platforms. Intel got tired of it and made AMD develop its own sockets, although they kept using the same footprint on the motherboard all the way up to Intel hauling out LGA775. When Intel abandoned Slot 1 for S370, AMD immediately switched from Slot A to S462.
Intel actually did allow Cyrix to continue to use Intel sockets going forward, showing that they didn't see Cyrix as a serious threat to them. When VIA ended up controlling Cyrix and its x86 license, they used it for years to make S370 and S479 parts before Intel called a halt to it.