Ok, DO NOT USE SOFTWARE RAID. Completely Lame and takes a big hit on proc performance. As for the server what do you plan to use it for? That should be part of the primary driver for spec'ing it out. RAID 1 is nice but your lose that second drive. I would recommend getting an adaptec RAID Card as you can add additional drives to your RAID 5 array on the fly and w/o rebuilding your array.

I'm a consultant in Microsoft technologies so I should be able to answer your most technical question so PM me if you have more. Cheers.

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