Why RAID is (usually) a Terrible Idea

What is the Problem?

So what do I have against RAID? I have no problem with the concept. The problem is that for 90% of the people out there, it isn't a good idea. Since high end enthusiast machines are some of our most common builds here at Puget, we frequently are asked to build machines with RAID when it doesn't make sense. I am here to say that those RAID configurations account for a very large portion of our support tickets, and are one of the biggest sources of frustration for our customers. I can also tell you that "I told you so" is not a very comforting reply from our support staff! Don't worry, that's not what we say (but there are times when we sure do think it!). That is the root of my problem with RAID -- I see the frustrations it causes all the time. When I weigh that against the benefits of RAID, I just can't recommend it except in very select cases.

The underlying problem with RAID is the fact that by using it, you are making your computer significantly more complicated. Not only are you now relying on two hard drives to work properly, but you are also relying on a much more complicated controller (the RAID controller). If any one of those items has a problem, the array fails. If one hard drive has a problem even for a moment, you have a degraded array on your hands. At that point, you are relying on the RAID controller for error correction and array management, and the fact of the matter is that all (yes, all) RAID controllers onboard a motherboard are low quality. They have been added to the motherboard as an afterthought -- a feature added simply because the manufacturer knows that if they add any feature they can, they're more likely to sell their product. At at a time when nearly every modern motherboard has built in RAID, they have to offer it just to be considered as feature rich as their competitors.

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