Well I want to use RAID 5 with my new 2k computer build as I heard it is the best RAID compared to the others. With RAID 5 you get both the speed and reliability. In Raid 0 you get the speed but you can lose data quickly. In Raid 1, you gain the reliability but you lose half your space(and lose speed i think?).
 
I was thinking about putting 3 of these wd 640gb hardrives together in raid 5. http://www.newegg.com/Product/Prod [...] 6822136218
 
But I heard you need a controller(wtf?) to use raid 5...is that true?
 
What else do I need to know?  
 
I also read somewhere that raid 5 isn't really praticial for consumers and if it would be better to use Raid 0+1 or something like that.  
 
Anyone know raid here? I need help lol. I thought most motherboards come raid equipped? and if it matters i am thinking about doing this mobo http://www.newegg.com/Product/Prod [...] 6813136042
 

You can use a on board RAID controller, but which board is it?  Thats the DFI search page on Newegg.

there we go fixed.

Why do you want RAID?  What are you hoping to gain with RAID?  Yes RAID 5 will offer more throughput than a single drive but will have worse access times for instance.  RAID 5 is mostly used for data redundancy so the failure of 1 drive will wipe out your data. If this is just a desktop PC you might want to do something different even if you do store valuable data on this system.  
 
In my system I use a single drive to boot and load apps, and I also have a RAID 5 array for my important data.  I also have a server with much more space on it but thats another story.

If this is for a personal computer, I would just ditch the raid setup, and get one Velociraptor and one huge 7200 rpm sata drive.
 
http://www.newegg.com/Product/Prod [...] lociraptor
 
Put the operating system and programs on the velociraptor hard drive, and throw files such as pictures and music on the other hard drive. Less complicated and easier to manage in my opinion.
 

Like rozar mentioned, you need to know precisely this:
 
Why you want RAID 5, or anything for that matter.
 
Is it just because you heard that it's "teh shiznit"?!  In that case, google RAID 5, read up on it, understand what it gives you, and ask yourself if you need it.  Also would be good to google pros / cons of it, or some such stuff.
 
Read up on why it exists and where it is most used.
 
And I think you will answer your own question.
 
I keep saying this to people like you - it's probably not a good idea to get technology you don't understand.  Educate yourself first / get the technology second.
 
Edit:
 
Here's the thing, in case I didn't make myself clear.  I'm not slamming you.
 
But any system planning / design should start at the problem, and end at the solution.
 
As in - figure out what you need.  Do you need storage?  Do you need fast storage?  Do you need large storage?  Do you need redundant storage?  Do you need storage back up?  What use pattern do you anticipate?
 
The answers to these questions will determine the solution.  There are various products out there designed to address these various needs, it's a matter of matching the best one for your specific need.

unless you need uninterrupted protection from hardware failure, then you really don't need to go with raid.  just go with single drives, and a good backup.  period.

That DFI board will handle RAID 5.  But what the others have said is pretty much true.  
 
I use a raid 5 setup with 4 500 gig Seagates, in my file server/storage box.  I store stuff here I do not want to lose, documents, movies, pics, DVD and CD images, that kind of stuff.  I also keep a spare HD on hand in case I lose a HD in my array and need to pop in a spare and then I replace my spare immediately so I am ready in case it happens again.
 
My main PC uses a single 250 gig HD.  However my next PC will probably use 2 250 gig Seagates in RAID 0 for a nice speed increase.  RAID 0 is fast, but if you lose a HD your boned, thats why all the important stuff goes on the server.

Yeah like I said Im a noob and not sure if I fully understand raid 5. From what I understand, I want RAID 5 because you can redundancy while retaining disk space(maybe a slight boost in performance? than a performance of a regular hardrive; not sure about this though)
 
Lets look at RAID 0. RAID 0 splits data accross 2 disks significantly increasing the performance of the hardrives rather than having them as separate drives. However, the downside to this, is that you get NO data redundnacy.  
 
Now lets look at RAID 1. RAID 1 takes the data and makes a carbon copy by mirroring the data. While this is good because you get the reliability warranty, you lose half the disk space. It is also costly if you want reliability and want the disk space.  
 
Now lets look at RAID 5. RAID 5 uses 3 or more hardrives and distributes parity data accross all of the hardrives. This way you can lose any hardrive and still have data redundancy. Because contrasing from RAID 1, you seem to get MUCH MORE space. It seems to be a much more cost effieicent way of having that reliable redundancy. You also get the performance of the RAID 0 as well. The read performance of RAID 5 almost matches RAID 0. It is much more cost effieceint that RAID 1 as you only lost like 25% rather than 50% of the data.  
 
So basically RAID 5 is the best of both worlds right? RAID 5 combines the peformance of RAID 0 while retaining the redundancy of RAID 1?
 
You see this is the reason why I want RAID 5. In this day and age of computers, hardrives die all the time. I don't want to be constantly worrying about backing up data because I won't know when a hardrive will die. I would rather not have to worry about that. With RAID 5, as long as 2 drives don't die at the same time(extremely unlikely), I will have 99% redundacy and never have to resort to backup methods.  
 
Sorry for not being exactly clear in my first post...but from what I understand(although I may be wrong on my research) this is what I want. What else do I need to know. Is my information correct?
 
Without RAID 5 (or RAID 1 I guess) you always have a chance of losing your data, and I never want that to happen ever again. I've had bad experiences with that.
 
Anyhow, thanks!

As a guess, if you need to ask the question, you don't need raid.
 
There is generally no real world(vs. synthetic transfer rate benchmarks) performance advantage to raid of any kind.    
Go to www.storagereview.com  at this link:  http://faq.storagereview.com/tiki- [...] iveVsRaid0
  There are some specific applications that will benefit, but
gaming is not one of them.   Even if you have an application which reads one input file sequentially, and writes
it out, you will perform about as well by putting the input on one drive, and the output on the other.
 
The value of raid-1 for protecting data is that you can recover from a hard drive failure quickly.  
  It is for servers that can't afford any down time.  
  Recovery from a hard drive failure is just moments.  
  Fortunately hard drives do not fail often.
  Raid-1 does not protect you from other types of losses such as viruses,
  software errors, operator error, or fire...etc.
  For that, you need EXTERNAL backup.
  If you have external backup, and can afford some recovery time, then you don't need raid-1.

"What is a z-j?"
 
"If you have to ask, big man, you can't afford it..."
 
What geofelt said.
 
PS.  Google is a powerful tool.  Wikipedia - or wherever else you got the definitions from - not so much.  It's even incorrect at times...

I don't understand why people are so damn negative about raid, I'm thinking about getting myself raid5 array for my next build later this summer. The reasons are pretty much the same as moomoopro's, extra speed and data redundancy without too much wasted space.
And I was eyeing the exact same HDDs as well. Those are 2 platter drives and are pretty fast just by themselves, put 3 or 4 of them in RAID5 and you got yourself a winner. and not too expensive.  
 
but yeah, some mobo chipsets will usually support raid levels 1, 0, 1+0 and 5. Depends on the southbrigde, intels ICH9R where R stands for raid support, can handle them nicely.
You'll get better options and slightly better performance with dedicated raid controller PCI(-e) cards though
 
according to wikipedia you'll get nearly the same read performance with raid5 as in raid0 array with same number of drives, write performance isn't as good though. Available size is (N-1)*Smin, where N is the number of drives in the array and Smin is the size of the smallest drive.

If you can afford it, do it. If you store vast amounts of data (specifically media servers) then its really your only option. I’m currently blowing out a 1.5 TB raid 1 and I need redundancy so I’m looking at 4 x 750 gig sata drives for raid 5 (2.1ish TB in the end). I even tried a 1 TB WD External USB drive for backups but it gets blown out.  Its a completely viable option if you want *more* data protection and money isn’t much of an issue. There’s good reasons why servers use raid, in the past 15 years I can’t tell you the number of times I have had my career saved by raid when a drive pops. Not one disaster yet! But it you are just talking about less then 500 gigs of data, just buy a 500 gig drive and a 500gig USB drive that you connect just to back up the HD on occasion.
 

I don't really "get" RAID in a PC anymore.  What good is having your data backed up on a 2nd drive if something happens to your PC ?  You can't access your data if applying the latest service pack fudged your box.  RAID on an NAS is another story.  If my machine goes south for whatever reason, I can access the NAS from any other box on the network.   In an NAS, fewer parts means fewer things to go wrong.
 
RAID also has some sophistication that, if you are asking the questions you are, it might not be a good idea.   Infrant's (now Netgear) RAID-X technology is much simpler from an administration standpoint.  A drive fails, you pop in a new one and it auto rebuilds and doesn't care if the replacement is the same size.
 
I used to build SCSI based RAID boxes but now I just build single drive systems with fast drives and store all office and personal data files on our 9 box SOHO network on an Infrant (Netgear) NV+.  Of course the NAS is in turn backed up and, short of a fire or terrorist attack, I can recover any file in seconds.  Recovery from a fire would take me an hour or so.

 
That's pretty obvious.
 
Please stop quoting wikipedia as a reliable source.  At one point it said that the population of African Elephants has tripled in the recent past, in the end.
 
And read some reputable sources, such as the storagereview site referenced above.  Maybe then you'd understand why the idea of software (onboard) RAID5 is fairly ridiculous, particularly on the desktop.

ruski, please stop telling me to search and instead help me. You seem to know a lot but you are not giving me information when I am providing enough information. You say search google, well guess what...wikipedia have the top 2 results. Whether or not you have had bad experiences with wikipedia, you have to admit, most of the information present(at least on the raid article is correct). So I don't really understand why you are discrediting it. Have you even read what wikipedia has to say? It pretty much matches the information found on "reliable sites" such as storagereview. Although wikipedia may be wrong on some accounts, can you please point out what is information is truly incorrect? It would help me out tons. *Note* I am not being sarcastic, I am serious. It would actually help me out and I'm sure others. Instead of searching aimlessly, you can just tell us!
 

 
Please tell me WHY exactly raid 5 is impractical on a desktop setup! I have enough bays and enough hardrives to do so, why should I not?
 

 
jack, This is why you partition your hardrives. If you make a partition for only your OS and you mess up your system by installing the latest service pack, nothing will to your other data. Only that partition which contains your OS will be corrupted.  
 

 
Isn't that what RAID 5 does? 1 hardrive dies, you just have to pop in another one and it will rebuild automatically since it has parity information on all drives not just 1. What is so advantageous of RAID-X technology?
 
The ONLY downside I can see with RAID 5 is the write performance is hindered.
 

 
How much slow down will you get from using software RAID 5? Is it really that significant? Any benchmarks or tests on this?
 
What kind of stripe size is recommended. Also, does anyone know how much slow down a system will experience. Anyone have any percentages or benchmarks? Also when? Just when saving files, installing or what?
 

 
This is exactly what I want. russki, do YOU suggest I use RAID 5? Or are those other various products that are better designed to fit my needs?
 
Also what are some examples of write-intensive applications? Is the slowdown really that noticable? Or is it more of in a server environment that it is noticeable?
 
And the raid controller on my motherboard, is that is a hardware controller? Its just not a dedicated pci-e raid controller? Will it be good enough? Or would you guy recommend a dedicated pci-e raid controller? Will there really be a significant difference between a dedicated one than one from a motherboard? Is there another motherboard that comes stock with a better controller???
 
Thanks!

I haven't checked Wiki lately, but it had perfectly accurate RAID info as of around 6 months ago (last time I checked). If I have a little time, I'll look over the wiki RAID article later and see if I can spot any problems right now, but on the whole, for factual information like this, I have found wikipedia to be quite reliable.

RAID 5 without a dedicated RAID card is somewhat slow on writes, especially small writes. It flies on reads, and does have a benefit in capacity and redundancy, but the write performance suffers due to the parity calculations. This is especially true when writing files smaller than the stripe size, as in this case, it has to write the new file, read the rest of the stripe, do the parity calculations once it has the full (new) data in the stripe, and then write the parity sector, while in RAID 0 or 1, it simply has to write, not do any reads or calculations. If some speed loss on writes is acceptable to you to gain more capacity and read speed than RAID 1 while having more redundancy than RAID 0, then RAID 5 could be right for you.

Well, RAID 5 does require a drive of the same size as the one that failed (or, more accurately, it can use a larger drive, but will only utilize as much space on any one drive as the smallest drive). If this so called RAID-X can use varying size drives, and fully utilize all the space, that is a benefit.

Read performance is almost unhindered as compared to a full hardware implementation, with the exception of high queue depth I/O, but write performance will be significantly degraded compared to a full hardware operation, especially with small random writes.