To my knowledge, the fastest Slot A (242 pin) CPU AMD ever made was a 1.1 GHz T-Bird. I had two Slot A's - one a 1 GHz Athlon and the other a 1 GHz T-Bird. It has a 200 MHz FSB, and the memory spec is PC-100 - but no more than 256 per slot for a total of 768.
I built a total of 6 K7M machines and all are in service today - extremely stable and much better with WinXP Pro than the K7V.