1. ## RAID Question.

How exactly does raid work? Say i buy 2x160gb SATAII hd's and put them in RAID-0, I was told i'll pretty much only have 160 gb's still, just mirror'd data and such, just a little confoozled

2. No... Raid 1 is mirrored. With raid 0 you will have almost the combined storage capacity. So two 160gb drives will give you around 320gb space. Of course you lose some in the formating.

3. Originally Posted by CGR
No... Raid 1 is mirrored. With raid 0 you will have almost the combined storage capacity. So two 160gb drives will give you around 320gb space. Of course you lose some in the formating.

you dont lose n e thing.... its just the units of measure become a little bigger... Hard driver manufactures work in a system of base 10... so 10^3 = 1000, but the only way a computer can look at it is in binary or base 2... so 2^10 = 1024 or the closest base 2 can get to 1000.... n e ways a drive says its 160gb in base 10 meaning very close to 160000000000 Bytes (160 x 1000mb/gb x 1000kb/mb x 1000 bytes/kb)... so now in computer lingo a GB = 1024mb, 1mb = 1024kb, 1kb = 1024 bytes. so all you have to do to figure out the formatted capacity is to take the number of bytes in base 10 and divided it by the units in base 2... in other words divide 160000000000 by 1024 3 times... gets you 149.01GB... you dont loose any space its just the units of measure become different size... its sorta like calling a kilometer a mile, and comparing that kilometer mile to a regular mile and saying that the distance just dissapears.

sorry i have always hated when ppl say they "loose space" when they format...

N E WAYS... there are many different types of raid but mainly ppl use raid 0 to gain performance because it will be using 2 drives in parallel, with raid 0 you double the number of GB's of the smallest drive. so in your caseu you would have 320gb of unformatted space or 298GB's of formatted space with close to twice the performance of a single drive. The only way you really get half the space is in raid 1 like the guy above me said...

4. Originally Posted by nd4spdbh2
you dont lose n e thing.... its just the units of measure become a little bigger... Hard driver manufactures work in a system of base 10... so 10^3 = 1000, but the only way a computer can look at it is in binary or base 2... so 2^10 = 1024 or the closest base 2 can get to 1000.... n e ways a drive says its 160gb in base 10 meaning very close to 160000000000 Bytes (160 x 1000mb/gb x 1000kb/mb x 1000 bytes/kb)... so now in computer lingo a GB = 1024mb, 1mb = 1024kb, 1kb = 1024 bytes. so all you have to do to figure out the formatted capacity is to take the number of bytes in base 10 and divided it by the units in base 2... in other words divide 160000000000 by 1024 3 times... gets you 149.01GB... you dont loose any space its just the units of measure become different size... its sorta like calling a kilometer a mile, and comparing that kilometer mile to a regular mile and saying that the distance just dissapears.

sorry i have always hated when ppl say they "loose space" when they format...

N E WAYS... there are many different types of raid but mainly ppl use raid 0 to gain performance because it will be using 2 drives in parallel, with raid 0 you double the number of GB's of the smallest drive. so in your caseu you would have 320gb of unformatted space or 298GB's of formatted space with close to twice the performance of a single drive. The only way you really get half the space is in raid 1 like the guy above me said...
You do lose some space. A 160gb drive will NOT format to 160gb. It will be in the 150's somewhere because of the cluster size.

5. Originally Posted by CGR
You do lose some space. A 160gb drive will NOT format to 160gb. It will be in the 150's somewhere because of the cluster size.

how so... my 200gb hitachi formats to 186.30gb... and acording to some simple math...

200 x 1000 x 1000 x 1000 = 200000000000 bytes

200000000000 / 1024 / 1024 / 1024 = 186.26 gb... i would have to say i dont loose a single thing!

cluster size has nothing to do with it... cluster size is just the smallest unit of space the drive allocates to be used... in windows xp its 4kb... so a 1kb file will use 4kb on the disk but you dont loose the space.

10 bucks says ur seagate formats to right around 111.75gb.

6. He's right you do lose some actual storage space to cluster size loss. It's not visible in the 'total formatted size' but what happens is, unless every file is an exact multiple of the cluster size which doesn't happen, every file or part of a file that doesn't take up a complete cluster wastes the rest of the space for the cluster in which it's stored.

7. RAID 0 is also called " Striping ", The RAID Controller will write to both drives at the same time, however your data will be spread across both drives. Some folks say it's playing with fire, since all your data is basically gone if one drive tanks. Though it is a performance boost. I just upgraded from a single WD 80gb to a pair of WD 36gb Raptors in RAID 0 and saw a pretty big "seat of the pants" performance gain. If you striped 2x 160 gb drives, than you'd be seeing about 320gb unformatted, 298-ish formatted as one single hard disk inside your OS.

RAID 1 is also called "mirroring" where the RAID controller writes to both disks at the same time, but instead of spreading out your data like RAID 0, it makes the second hard disk an exact copy of the other. This is where people think they "lose" hard disk space. A mirrored array will only show up as one hard disk: ex. 2 x 160gb drives in RAID 1 will show up as a single 160gb drive... even though there are 2 drives in the machine.

If you go RAID 0, do regular backups and keep your data safe on an external hard disk or something.

cheers!

~ Gos