The Xeons can have up to 2048k cache at 1024k one
start  to get good performance
A PII-450 with 512k cache with an FSB of 124 or 133
gives really good performace doesn't hang as easy
playing games as
a celery 466 @ 832  with measly 128k cache 
and gives better performance.
Cache is nice but also what makes the xeons expensive.