Hi Ed,
You need to look around in the forums using "search". type 5400 or UDMA to
get results. I can't remember right off where I went for detail info, but
the info was that the new 66 UDMA and 100 UDMA works if you have a 7200 rpm
drive.  Otherwise there is no advantage over 5400.
Go the the link below and search using 5400 as target. Several discussions
on the differences.

http://sysopt.earthweb.com/find/ssmain.cgi?results=0&query=5400+rpm

God Bless, and have fun.
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