must FSB speeds match?

Processors list a FSB speed, and motherboards list a FSB speed. RAM also has a speed, although for some reason the units (MHz) are usually left off.

But I'm wondering, do all these speeds have to match? Or, if a slower item is paired with faster items, will they all just use the slowest speed?

Example: If you want to use a processor that has a 1066MHz FSB, do you have to use DDR2 1066 memory and a motherboard with a 1066MHz FSB?

We already had this thread.
/comp/ is that way ---->