Greetings, George!I'm no expert, but just a user full time.
Re: PC100 ram vs PC66. I have a mobo that came with PC66, 64 MB. I took that out and installed 192 MB of PC100. I no longer get the error messages I use to get and everything runs much smoother, especially with multiple apps open. Best move I've made so far.Hope this helps. Degraded, not that I am aware of. FSB is fixed by the processor far as I know. Hope this helps. -v-

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