By claiming others don't know what they are talking about you are basically implying that you do, right? Well, apparently you don't and you are also incredibly rude. Hardware RAID certainly doesn't scale until the bus' limit is reached; the controller chip often craps out before that, although when using a high-end controller like an Areca 1210 you only hit this limit with 4+ very fast drives like the new Raptors or SSDs
I too see no reason to not use the onboard RAID controller when you are using RAID 0 with 3-4 drives max. The Intel ICH9 is a perfect controller for this application. It's okay for RAID 1 too for most users.
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