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I have a WD 74GB Raptor with Win XP Pro installed, and have 2 WD 320GB Caviar's installed. (Hopefully in a RAID 0 config.)

In Device Manager under Disk Drives it recognizes the 2 WD 320GB drives as NVIDIA STRIPE 596.18G

My question is; Shouldn't it say half of the total GB in a RAID 0 configuration?

Thanks

no, Raid 0 is disk striping, it distributes the data across both drives but provides no fault tolerance. The whole intention of this is performance, nothing more.

What you are mentioning is Raid 1, also known as mirroring. This copies the same data to both drives, in case of failure of one drive, you can replace it with one of greater or equal size and rebuild the array.

I am unsure of which one you are going for, let us know

I'm going for RAID 0 as mentioned in original post. I just want to know if I have two 320GB hard drives, will the value of the of the total in RAID 0 be 320 or 640? It is currently showing 598.18GB (basically the total of the two drives)

I know for sure that it is stiped and the two drives are definately one now. I thought when you use a RAID 0 configuration, you use two drives for the capacity of one?

In Raid 0, you do use two drives and they are seen by the OS as one drive, but the capacity would be the total of the two drives.

In Raid 1, which is mirroring, your two drives would have the same capable storage as the lowest capacity drive in the array. So if one drive was 120 and the other was 160, it would be 120 that would be usable.

So if Raid 0 is what you want, it is exactly what you have. I think you are just getting the different types of Raid confused

Go here:
http://en.wikipedia.org/wiki/RAID

That will explan a little bit about how different levels of Raid works.

Thanks. I do have the right setup then. I never did a RAID setup before, and I just wanted to be sure. I wanted my 74GB Raptor to boot Win XP pro, and wanted the 2 320GB Caviar drives to run RAID 0 to be fast. (don't really care about the backup thing of mirror, like RAID 1) So thanks for the clarification.

Well for some it is important, for example, if one of your drives in the Raid 0 fails, you lose everything, which is twice as much as then if they were single drives.

Like Zyfer said, be aware of the data loss risks. You actually more than double the odds (statistically) of losing your data due to drive failure by going RAID 0. Make sure you have a sound backup strategy.

Where did the extra 40 Gigs go? 2x320=640. Even if you divide 2x320 by 1024 you should get 625 and not 596.

That is just because today's hard drives are really less then they say....

It is getting worse as they get larger

Capacity measurements

Hard drive manufacturers typically specify drive capacity using 'SI prefixes', that is, the SI definition of the prefixes "giga" and "mega." This is largely for historical reasons, since disk drive storage capacities exceeded millions of bytes [4] long before there were standard 'binary prefixes' (even before there were the SI prefixes, 1960). The IEC only standardized 'binary prefixes' in 1999. As it turned out, many practitioners early on in the computer and semiconductor industries adopted the term kilobyte to describe 210 (1024) bytes because 1024 is "close enough" to the metric prefix kilo, which is defined as 103 or 1000. Sometimes this non-SI conforming usage include a qualifier such as '"1 kB = 1,024 Bytes"' but this qualifier was frequently omitted, particularly in marketing literature. This trend became habit and continued to be applied to the prefixes "mega," "giga," "tera," and even "Peta (prefix)."

Operating systems and their utilities, particularly visual operating systems such as Microsoft's various Windows operating systems frequently report capacity using binary prefixes which results in a discrepancy between the drive manufacturer's stated capacity and the system's reported capacity. Obviously the difference becomes much more noticeable in reported capacities in the multiple gigabyte range, and users will often notice that the volume capacity reported by their OS is significantly less than that advertised by the hard drive manufacturer. For example, Microsoft's Windows 2000 reports drive capacity both in decimal to 12 or more significant digits and with binary prefixes to 3 significant digits. Thus a disk drive specified by a drive manufacturer as a '30 GB' drive has its capacity reported by Windows 2000 both as '30,065,098,568 bytes' and '28.0 GB'. The drive manufacturer has used the SI definition of "giga," 109 and can be considered as an approximation of a gibibyte. Since utilities provided by the operating system probably define a gigabyte as 230, or 1073741824, bytes, the reported capacity of the drive will be closer to 28.0 GB, a difference of well over 7%. For this very reason, many utilities that report capacity have begun to use the aforementioned IEC standard binary prefixes (e.g. KiB, MiB, GiB) since their definitions are unambiguous.

Many people mistakenly attribute the discrepancy in reported and specified capacities to reserved space used for file system and partition accounting information. However, for large (several GiB) filesystems, this data rarely occupies more than a few MiB, and therefore cannot possibly account for the apparent "loss" of tens of GBs.