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Anyone explain RAID?

By henrychieng
Mar 12, 2002
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  1. Sasquatch

    Sasquatch TS Rookie

    I noticed in one of the articles I read that the performance increase was significant with some apps, almost non-existent with others. Wouldn't increasing the RAM or bus speed yield similar speed gains?

    I also don't see any cost benefit to RAID. Four 120GB drives will cost more than a single 500GB drive. You'd actually need at least five 120GB drives to backup 500GB worth of data (well, only 480, but who's counting?) with a RAID 4 or 5 array.

    Definitely think I'll stick with discrete drives and partitions for various purposes.
     
  2. Rick

    Rick TechSpot Staff Posts: 6,305   +52 Staff Member

    Yeah, the performance gain is minimal for typical use. The thing about RAID 0 is it can effectively double your sequential transfer rates... The problem is for typical computer use, sequential transfers are rarely a reality.

    RAID 0 does not really improve random transfers, which is what most real-world usage relies on. So what you end up with is speedy transfers for huge, contiguous files, but average rates for opening applications, browsing the net, playing games etc...
     
  3. Surkitz

    Surkitz TS Rookie Posts: 171

    my question is do you have to even use RAID to have more than one HDD on your system work? for example: can i add another 120gig hard drive to my system and say, ok...done
     
  4. Mictlantecuhtli

    Mictlantecuhtli TS Evangelist Posts: 4,919   +9

    No, yes.

    You can add as many hard disk drives as you like and they don't need to be "raided".
     
  5. Surkitz

    Surkitz TS Rookie Posts: 171

    well thats good to know then. but it just sounds too easy for me to say ok ill plug this cord in the hdd and boot 'er up and windows recognize it.
     
  6. alphnumeric

    alphnumeric TS Rookie Posts: 209

    Your motherboard BIOS has to see it before windows ever will. Also it wasn't that long ago that consumer motherboards didn't have RAID built into them. All you had was your standard IDE controllers. The first RAID setup that I used was an add in IDE PCI card that had it's own BIOS. I could run it as RAID or as a normal IDE controller. As far as I know todays motherboards with RAID can be run as RAID or non RAID depending on how you set it up in the BIOS. For IDE you can connect 2 devices per channel (cable), one master and one slave. And with SATA 1 device per channel (cable).
     
  7. Insomnia

    Insomnia TS Rookie

    If I re-install Windows now, and get another HD to run in RAID next week, do I have to re-install again?

    I want to run in RAID 0. I can run 0, 1, 0+1, and 5 with the controller on my moherboard.

    I just slipstreamed the RAID Drivers in a new Windows XP Install CD.
     
  8. alphnumeric

    alphnumeric TS Rookie Posts: 209

    Yes, I'm fairly certain you will have to reinstall windows again.
     
  9. sliderule101

    sliderule101 TS Rookie Posts: 18

    I have several RAID (Redundant Array of Independent Hard Drives or Redundant Array of Inexpensive Hard Drives), the terminology gets changed over time. RAID sets vary depending on the type of RAID and the implementation. On most motherboards the array is 0 & 1, where 0 is not really RAID. It is a set of striped drives.

    Striped Drives involves no redundancy. Files are broken into stripes of a size dictated by the user-defined stripe size of the array, and stripes are sent to each disk in the array. It does not provide fault tolerance, but does increase the read/write speed.

    RAID 1 is usually implemented as mirroring; this is a set of drives that duplicates the data to both drives at the same time. Should one drive fail the other drive takes over which is fault tolerant. The overhead is 50%. Overhead is the amount of loss occurring from making the system fault tolerant, or capable of recovering from a hard drive crash. In this case two drives are required because of duplication of data only one will appear the other is like a backup.

    There are many flavors of RAID, for Servers or Enterprise storage I like RAID 5, 6, or 10. These require controller cards and are for usually used in large storage of data exceeding a Terabyte.

    Adaptec, 3ware, Perc4 are all good controllers for this application.
     
  10. Klaian

    Klaian TS Rookie

    I have a question. I am setting up a raid 0 system, and got everything set except making it bootable. It has N/A listed and bootable with the option at bottom of screen grayed out. What am I missing here?
     
  11. baller979

    baller979 TS Rookie

    When a raid 0 is setup up with two 74 gb hdd. will it show up in my computer as 74gb or 148gb?
     
     
  12. alphnumeric

    alphnumeric TS Rookie Posts: 209

    148 gig for raid 0.
     
  13. manacloud1

    manacloud1 TS Rookie Posts: 45

    question

    hi,

    im trying to setup windows xp with two sata drives set on raid. Everything is enabled in bios, and fine. I have also tried setting up third party drivers for the mobo. The hds cannot be detected.
     
  14. champmanfan

    champmanfan TS Member Posts: 59

    You need to format the HD using your mobo SATA setup so that means lossing your data but you can setup everything in there so you can either use RAID or mirror it. Thats what I did when I built my PC with the 680i SLi mobo, 2 WD Raptors Ent. & 2 seagate Sata 2 HDDs.

    My other PC could see the HDD without mucking about with formatting in BIOS but its something to do with the intergrated RAID controller in most mobos now.
     
  15. manacloud1

    manacloud1 TS Rookie Posts: 45

    heh

    thanks for the reply, I figured it out. I had the wrong controllers.
     
  16. hugzam

    hugzam TS Rookie

    RAID 0 - One drive and then add the other?

    For a RAID 0, If I already have a partitioned drive and no RAID, can I add another drive to make it RAID 0? Will the two partitions and the software that I already installed spand to the new one?
     


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