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| Please note: Do It Yourself articles and guides are intended for technically advanced users. Please review important cautionary information at the end of this page. Republished articles presented in the Do It Yourself section do not necessarily reflect the opinions or positions of AMD.
RAID
A redundant array of independent disks (RAID) is a configuration of two or more disk drives designed to provide improved performance and, in one setup, to recover automatically from a failure. Most commonly used in server applications, RAID can also provide enhanced performance and security for personal computers. RAID systems can be implemented at two different levels: RAID 0 and RAID 1.
RAID 0
RAID 0 provides data stripping – it takes data that needs to be stored and distributes it evenly between two or more hard drives. Because the system considers the two hard drives as one logical hard drive, the data is stored only once.
In a two-drive setup, for example, RAID 0 saves and accesses data quickly and efficiently. Rather than one bit at a time, RAID 0 stores and retrieves two bits of data simultaneously. Theoretically, the time it takes to save and access information is cut in half over a single drive system.
RAID 0 is popular for video and image production and editing, pre-press applications, and other applications requiring high bandwidth. However, RAID 0 does not provide fault tolerance – if one drive fails, the information on it is lost.
RAID 1
RAID 1 provides “disk mirroring,” which copies the same data onto two or more drives. Unless the system uses RAID 1 with duplexing, both drives must use the same adapter card.
Unlike RAID 0, RAID 1 allows for fault tolerance. Since the same data is saved twice, if one hard drive fails the second has a complete copy of all information saved. While not as fast as RAID 0, RAID 1 retrieves data more efficiently than a single drive setup because information is gathered in from more than one location.
RAID 1 is popular for accounting, payroll, financial, and other applications that require high availability and higher relative data security. However, RAID 1 writes data once in each drive, which makes saving data less efficient and halves drive capacity.
Setting Up RAID
To use RAID, a system’s motherboard must have an onboard RAID controller or a PCI-connected RAID controller. Additionally, its hard drives must be compatible with the motherboard, and preferably all of the same brand, model, and size. Most RAID-controller-equipped motherboard manuals describe how to set up RAID, and many ship with user-friendly setup utilities.
Cautionary Statement
Activities and projects described herein may involve the use of tools and materials that may present health and safety hazards. These must be handled carefully and all tools and products should be used strictly according to manufacturers’ precautions and instructions for the safe use of the respective tool or product. The techniques described herein may result in the voiding of manufacturers’ warranties. The user assumes all risks associated with the techniques described in this article/guide. THIS INFORMATION IS PROVIDED “AS IS” WITH NO WARRANTY, EXPRESS OR IMPLIED. AMD ASSUMES NO RESPONSIBILITY FOR ANY ERRORS CONTAINED IN THIS ARTICLE/GUIDE AND HAS NO LIABILITY OR OBLIGATION FOR ANY DAMAGES ARISING FROM OR IN CONNECTION WITH THE USE OF THIS ARTICLE/GUIDE.
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