To quote a friend of mine from a different forum:"On a relatively fast CPU with fast memory, RAID 0 helps quite a bit. Most PCs have "fake hardware RAID" so the CPU does most of the work of RAID rather than the RAID "controller". A "fake hardware RAID" controller is just a set of normal SATA ports and special software in the BIOS and OS driver to make them appear as one RAID array.It's not exactly true that RAID 0 doubles your failure rate. MTBF is measured in time and probability. Using RAID 0 does not cut the time in half. An accurate MTBF calculation has to include the probability of failure along with the time. As the drives get older the probability increases in a non-linear way, and the probability is twice as high for RAID 0. At the beginning that doesn't make much difference (0.01% versions 0.02%). As the drives get near the MTBF (Mean Time Between Failure) then it becomes more important to replace them before they fail or keep a data backup. When the probability is like 5% then the difference between 5% and 10% can make a huge difference.In my opinion the software MTBF is much higher now than the hardware MTBF. Except for older drives, one is more likely to lose data due to software errors. RAID 1 doesn't help recover data lost by software errors, since both copies are usually incorrect in the same way. In any case, keeping a backup copy up to date is essential.It turns out that RAID 1 is nearly as fast as RAID 0 when looking at Windows. Windows uses delayed writing. The overlapped reads of RAID 1 are as fast as RAID 0 and the extra writes of RAID 1 usually don't slow down applications unless the write a lot of data (enough to fill up the file cache in RAM). Mostly RAID 1 is more expensive since it doubles the cost of storage. RAID 0 increases the cost of storage somewhat unless the drives are already as large as economically possible. RAID 0 and JBOD (Just a Bunch Of Disks) have the same failure issues so one might as well use RAID 0.My problem with RAID 1 has been the horrible RAID synchronization software provided by Intel. It gives one little or no control over how and when the arrays are synchronized and interferes with normal operation. Because of that I finally just started using RAID 0 and doing my own backup. I had more problems with the RAID arrays being out of synch than I did with actually needing RAID to recover from a drive failure.With multi-core CPUs becomming common I think that RAID 0 will become increasingly necessary for the file access to keep up with the processing. What would be even better is a new storage technology that is faster than hard disks, less expensive and more dense. SSDs so far have not been less expensive nor denser, although they are faster at reading."He phrases things far more eloquently that I can.
