Theoretically, if you have a file that is split on 2 drives it can be read simultaneously from both drives. If you defrag that array, I'd guess that the file is then combined into one contiguous file ...

I've been running an Abit A7V with a built in Highpoint 374 RAID controller for a while. I used a RAID 0+1 array thinking that I would be able to survive a dead drive due to the mirroring. Long story ...

While RAID 5 isn’t exactly the Holy Grail of desktop NAS, it is a very attractive option that combines the speed of striped RAID 0 and sufficient data protection without a humongous loss of storage ...