1.) Use RAID 0 so that all three drives act as a single drive. You would benefit from a speed increase, but if one drive fails then the chances of recovering your files are slim to none.
2.) Use RAID 1 on two of the drives, having one be an exact replica of the other. This protects against hardware failure but not electric shock, malware infections, or accidental deletions. You could then use the third as an independent drive that has no mirror. (For downloads, temporary files, your paging file, etc.)
3.) Use JBOD (not an official RAID level) to use all three disks as one. You would not benefit from a speed increase as you would with RAID 0, but if one drive fails then your chances of recovering other files are good.
4.) Don't use RAID at all, with all three drives being independent of each other.
5.) What I would do: Install the two like drives in RAID 0 to maximize performance and volume, then insert the third into an external hard drive enclosure and use it for regular backups. This gives you the best of all worlds, ensuring you maximum use as well as a secure backup in case anything happens to your computer.
Hope this helps,
John
I am currently building a computer. I bought three Western Digital SATA hard drives. My question is if I have three drives, and they all have the same speed, same size, and same cache, will I be able to use them in RAID setup? Two of them are plain- Jane models, and one is a Caviar model. Will this make a difference? Also, will I be able to use an odd number of drives in RAID? Your help is greatly appreciated. Thanks.

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