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> I recently bought a new Abit board at a computer show and the guy tried to
> talk me into spending 30 bucks more on the RAID version. I decided against
> it but now I'm wondering what RAID could do. It has something to do with
> mirroring the hard drive, I know that, but would it help to have it on my
> home PC?
RAID 0 will "mirror", or write to two "identical" drives, the data.
This will tend to slow the system down slightly, but it means that it can
READ faster and that if a drive dies, you can keep on running.
RAID 1 will split the data across multiple drives, binding them into
a larger logical drive. This will tend to speed the system up, but makes
the data more friable in that if ANY drive dies, ALL the data goes away.
RAID 0+1 (aka "RAID 10", although there IS no such thing) is a RAID
0 of a couple of RAID 1 sets. Or a RAID 1 set of a couple of RAID 0s -
depending on your viewpoint. You get the improved speeds of RAID 1 and the
reliability of RAID 0. At a cost, of course - it takes four drives to RAID
0+1.
None of the IDE RAID boards I've seen seem to offer RAID 5 - where
they take at least 3 drives (I like to use 5), and "stripe" the data so
that, with 5 drives, they write four sectors out to four drives in parallel
and CRC data to the fifth drive, but they move which drive IS the fifth
drive a sector at a time.
This means that the CRC sector "barber poles" around the logical
array of drives.
Your storage for "N" drives is "N-1 * capacity" where the capacity
is the capacity of the SMALLEST drive in the set.
However, if ANY drive dies, the data sectors can be recreated by the
CRC data, and the CRC info can be ignored if it is what is missing.
RwP
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