Here's the deal as I see it

The processor speed, and the memory speed are both set to 133Mhz double pumped. That is, data is sent on the rising and falling clock edges. So they are synchronous. However, there will be at least one chipset that will allow you to set the FSB asynchronously (the KT266) letting you use PC2100 (DDR PC133) with a 200 Mhz FSB (100 double pumped) or allow you to use PC1600 (DDR PC100) with a 266 Mhz FSB proc (133 double pumped.)
Did any of that help? Sure hope so
Cheers -Ben-
P.S. the multiplier you'd be after is 9.0 (133X9.0=1200)