If we look at the chapter on reliability, the more parts involved the more likely we get a failure, so for reliability the single drive wins. For speed the RAID 0 wins.
Since you didn't detail your goals, this should help you decide.
Bob
is it better to have 2 seagate barracuda's 7200.9 200GB 8MB cache in raid 0 or a single seagate barracuda 7200.9 400GB 16MB cache? i dont want the perpendicular tech HDD's until its more mainstream. this will be on an nforce4 mobo, so maxtor isn't an option. Western Digital doesnt support NCQ and their system for measuring HDD space is different from the rest.

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