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clarification on Raid5 and drives to be used

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May 18, 2006 9:50:16 PM

Hi,

I just wanted to be absolutely certain before i go opening up 2 new HDD's ive ordered.

The Mobo manual says that for Raid5 (possibly others too, i dont care atm) that it needs "a minimum of three identical hard drives" and i just wondered how identical do they mean?

I thought i'd got the exact same model, im already running a WD200JD and i've just ordered and received 2x WD2000JS drives.
Both SATA, 200gb, WD hard drives, but obviously if that lousy letter is going to f**k me over then theres no point in opening up these 2 new HDs if i cant run all 3, i'd sooner mail them back and scrap the idea for now.

Im guessing by the FAQ saying 'mixed sizes uses the smallest for all drives' that im fine, but while there wrapped up and i cant build the rest of the machine till the f**ker who sold me an 2nd hand x1900xtx listed as new and decided cos i didnt want it when i found out 15min later he'd lied (he'd bought it off ebay himself!!) he's now reselling the card and keeping my money, and paypal are useless till 10 days is over! so im sat waiting for paypal to get my money of the spotty lying POS :( 

anyway hehe, safe or no use?
May 19, 2006 9:59:51 PM

What he said, except I vote for RAID1 (mirroring).

Actually there are a few RAID 5 motherboard controllers that actually offer suprisingly good performance on sythetic benchmarks.

But it does seem that motherboard RAID 5 controllers seems to screw up more often than hard drives fail. Also if the motherboard/controller fails finding a compatible rcontroller for you RAID 5 array is problematic.

RAID 1 or RAID 5 is no substitue for a sound backup strategy, but keeping the stuff you can't afford to lose on a RAID 1 array is an extra level of protection against data loss between backups.
May 19, 2006 10:16:37 PM

How would I be with a $50 raid card? theres no way i can justify $150-250 on a true controller, i just want something there constantly keeping data safe and those sort of figures i'll stick to doing it manually i think.

All im looking for is something to keep files nice and safe, and if i can get a little bit of a speed increase from it then thats even better.

Could someone give me some examples of how these budget cards would effect me in real world situations ie gaming (like loading BF2 maps), creating large RAR files (say 300mb), unpacking large rar files (again 300mb) and windows load times.
Which would be faster, slower, no different/barely noticable etc

Granted paying for a real card would be a win win but im not ready to throw £100 at one just yet, not for a home computer, but maybe at a later date it could be worthwile if i can be convinced its needed.

p.s.
How long does it take to get used to this f**king forum having a 'new topic' button where i'd expect the 'reply' button to sit :p 
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May 19, 2006 10:50:49 PM

Cheap raid cards are mostly crap, similar if not identical to the sil 3114 raid5 on newer MB's. Get a highpoint 2320 and you get a solid raid 5 controller that has faster performance with 3 hd's in raid5 than the onboard sil or nvidia with a 2 drive raid0, and it's redundent. Otherwise throw all three in a raid 0 and tear it up. Just my opinion.
May 19, 2006 11:15:59 PM

So whats the cheapest hardware raid card capable of Raid5 on SATA
Is there a clear way of identifying them asside from the pricetag, as i've seen one at £100 which could be managable, but if thats just a fancy cpu powered one it can get stuffed!

I can raid0 with three drives? always assumed that was limited to 2 drives.
Are these negative comments about Mobo Raid purely based on the Raid5 setup, or is it the same with all types?
May 20, 2006 1:20:50 AM

The best way is to check the chipset used. The highpoint I mentioned has a hardware xor chipset which speeds up raid calculations, it's the lowest price hardware card I could find; it's pci-e 4x. the nvraid implimentation can get you over 300+ meg per second if setup with the right drives. I have two samsung sp2504's in raid 0 on the nvraid and get 110 average read and burst of 242.8 with hdtach. Course is you use other benchmarks like ATTO I could say I get:


1GB/Sec write's YeeeeeeHa!!!!

Anyway, the Raid 5 on the highpoint is a bit faster at times, a bit slower, the burst is certainly slower though. Thus 3 hd's in RAID0 on an nvraid will just cruze.
May 20, 2006 1:40:37 AM

HOW MUCH!!! Christ, im not made of money!!
£190 is the cheapest i can find, and im looking for something that at the absolute maximum hits £120/$200. (£140/$260 on newegg)

I guess hardware isnt an option then, afterall i just want it for the extra peice of mind, would a cr***y CPU powered card do the job?
I'd prefer to use the raid on the asus board (P5WD2-E Premium) which i think mentions:
ICH7R
Marvell 88SE6141
Intel Matrix Storage technology

One of those im guessing refers to the Raid controller im guessing? If thats too unreliable to consider worthwhile (sod slow write speeds & CPU useage) then how would things differ compared to the sil 3114's which i remember hearing a while back werent all that bad (write tests asside).
Hardware is definately not an option, and while Raid0 on 3HDD is appealing, its not what i was looking for really.

Also, on the original point, im fine using 2x WD2000JS with a WD2000JD right? Its not THAT fussy about whats used.
May 20, 2006 1:59:04 AM

You could just as well use a 60gb maxtor, 200gb wd, and 750gb seagate and get a raid array out of them, but it's limited by the smallest. My controller was a couple hundred, not really needed for what you want. Just run a raid 1 off any integraded controller and you'll be fine. Use the 3rd drive for swap space and data storage.
May 20, 2006 8:08:30 AM

Hmm, if i understand it correctly, it'd take my 2x 200gb drives, create a 200gb Raid0 and a 100gb Raid1.
I've still got 200gb sitting on there which could be 'destroyed' at any second, but I also have 100gb which is completely safe.

So rather than using Raid1 and having purely 200gb backed up at all times, I get half that and theoretically I get a whole drive running Raid0.
my only concern would be that whatever goes onto the 200gb Raid0 area, its not going to be safe, it would be no better off on any one of my other drives.
I've got 760gb over 3 drives and an external drive, with 2x 200gb which i want to use to make that 400gb in R5 + 560gb standard.
I do have a 4th 200gb which is a Cuda, i maybe i can run a dual Matrix giving me 400gb R0, 200gb R1 and 360gb.

It still doesnt sound a better option over Raid5, because i'd rather have the 400gb completely safe, im hardly short of storage space, but i'd be short of secure space.

Are the Sil 3114's any more/less trustworthy than my on-board setup?

A 400gb Raid5 is much more appealing than 2x 200gb Raid1, or a 400gb R0 + 200gb R1, but I cant afford the hardware controlled prices and if on-board is too dangerous and cheaper CPU powered controllers arent any different, then im not sure what i'll do.
May 20, 2006 8:33:34 AM

Scavange the cash, I've got 4 320's in raid5 and it's been working sweet for 6 months. Granted the sil 3114 will probably work too, I wouldn't have any reservations using it, just be careful to install the drivers as cleanly as possible and make sure they are the most recent from sil, not the mb or add in manufacturer.
May 22, 2006 8:18:53 PM

Hello again :) 

Michael, that highpoint 2320, theres one on US ebay (actually theres 98!) for $290 and having just got my money back from the c**t who kept my x1900xtx payment, along with a few orders and another one hopefully in the next week means i can actually afford to get one of these right now, and despite them being f***ing expensive (:p ) im hoping that it'll be a worthwhile investment.

could i ask you a couple of questions regarding this card?
Whats so special about that specific model, compared to the 2220 & 1820A which the seller also has (at $280 & $250)

They claim to be PCI-X and PCI backwards compatable, now i have 2+2 lots of PCI-Express slots (2 full size, 2 mini - wtf are they for?!), so would these fit into a PCI slot, or one of these PCI-Express slots? (there site lists PCI-X and PCI-Express as 2 catagories).

The 2320 (possibly the other 2 as well) are SATA II, however of the 3 drives, it seems the older one is the original SATA, and that extra letter on the end of mine probably is what describes it as SATA II, is there going to be complications/incompatabilities from this?

If it would all be fine, i'll probably get it ordered this week once ive heard how much shipping would be and if the nice gentleman would be a little discreat with certain values ;)  hehe
May 22, 2006 8:47:18 PM

PCI and PCI-X are compatibly, most of the time, no PCI-Express card will work in the previos two, it's a serial interface wheras the others are parrallel. Check your MB manual and see what the pci-express slots are, if there are two "full-size" I assume you mean 2 16x slots on an SLI board, and two "mini" would most likely be 1x slots.

The 2320 is a 4x card capable of being put in a 8x or 16x slot so if you don't have two video cards you could use the other 16x slot. If you don't want to do that you should get the PCI version which is the 2220 and 1820, I don't know the specs of those off the top of my mind but they won't have the throughput you would need for more than 2 or 3 drives as they only work on the PCI bus, unless you somehow have pci-x 100Mhz or 133Mhz slots which I doubt.

The 2310 might work for you instead, again the 4x pci-express card (works on 8x and 16x also) but only 4 ports instead of 8, might be able to find it cheaper.
May 22, 2006 9:47:19 PM

Raid5 is only for you if you need lots of capacity and to keep your machine going during a failure. R5 performance with fast drives is pretty much governed by the strengh of the controller wich has to perform on the fly parity calculations - cost is certainly a factor here.

A good cheap use of the 3 drives would to have a pair Raid0 and occasionally run a ghosting tool to plop a compressed image onto the third. Or go R1.

btw, WD released a series of drives named Raid Edition (RE). According to the blurb problems can arise Raiding 'normal' desktop drives as occasionally they perform thermal calibration during which reads & writes cannot be performed. The problem arises as the Raid controller thinks the drive has failed.

Never had an issue with my own Raid encounters over the last 5 years however........touchwood!
May 23, 2006 1:22:08 AM

RAID 5 is only more reliable if the controller is more reliable than the individual hard drives.

Technology advances, but for now cheap RAID 5 cards are by most people's estimates far less reliable than hard drive

So if you want cheap reliability go with RAID 1 becaues if you controller screws up you end up with 2 identical hard drives each with all your data and fully readaby by any NON-RAID controller.

If you want cheap speed and dam the risks chose RAID 0.

That Intel Matrix solution sounds very interesting. It has me hoping that Intels Next Gen beats AMD so I have an excuse to start building Intel boxes again.
May 23, 2006 1:43:43 AM

I'll take a look at that 2310, not sure if i'd ever need more than 4 drives running off there, however 5 would have been nice.

Running Raid5 with 4 drives, how would that differ to running with just the standard 3? I cant say i understand the term 'hot swappable' which seems to pop up fairly frequently, it sounds too similar to USB's 'plug n play' and im pretty sure plugging and unplugging SATA drives randomly whilst doing stuff isnt going to go down too well :) 

If i can find a 2310 on ebay (unlikely, and i prefer ebay cos they take paypal, dont have a credit card to purchase from overseas) then if theres a noticable price difference i'll go with that, otherwise i'll more than likely end up getting the 2320 if thats one you've got and would recommend.

btw, Mobo manual says:
2x PCI Express x16
1x Universal PCI Express (max x2 Mode)
1x PCI Express x1 slot
3 PCI Slots

I have no intention of going to Crossfire/SLi so that 2nd slot is free for a Raid card or anything else if it ever arrived.


Regarding the other comments, I just dont like the idea of Raid 0 its just far too risky on a machine i use for work and gaming. Raid 1 seems kinda wasteful not that im short on storage space, I just feel that Raid5 would offer an improvement in all areas, giving me the security of knowing theres 3 drives working together incase 1 fails, and also because i get to see some data transfer improvements (tbh ive no idea how significant these would be!!).
Intel's Matrix does sound like a very good idea though, but im quite a horder of junk files and i'd much rather know i've got 3 hard drives full of c**p safe and sound, than only 1/3 of my storage space being safe.

As soon as i read about Raid5 a while back i knew it was something i wanted, i just never expected i'd end up paying £180/$320 for it after buying the drives (i've purchased 4 in the last 6 months, 850gb in total, and selling 2nd new 500gb ATA drive atm for a fraction of its worth!)
May 23, 2006 2:06:00 AM

SATA is hot pluggable, if a drive fails on my array, I unplug it and plug a new one in, while everything is running, and it rebuilds it. The hot spare is simply a drive that does nothing until a failure occurs, then it automatically rebuilds to it with out you having to swap it out.
May 23, 2006 5:07:30 AM

Plug and Play isn't a USB feature. Its ..

Quote:
A standardized interface for the automatic recognition and installation of interface cards and devices on a PC


And it works pretty good since I haven't had to manually set IRQ or Memory Address Ranges when adding a PCI card since 1996ish.
--

Hotswapping means you don't have to shut down windows, connect the device, and boot windows.

When you have a hotswappable device you get a "safely remove" icon in the system tray. You are supposed to request permission to remove the device before unplugging it.

This prevents you from removing a hard drive before the file table hasn't been updated, the write cash hasn't been flushed, or while any of its files are locked (in use).

Sometimes a file will get stuck in the locked position preventing you from deleting it or removing a storage device.

There's a neat little utility called unlocker which will unlock any file or directory when such problems occur.

--
Hot spares are nice because with RAID 1 or RAID 5 you normally only have one redundant drive. So if one drive fails, then another before you replace the first and give it time to rebuild you are in trouble.

When you start adding 10+ drives to an array the chance that two could fail in a row increases, but for a 3 drive array I think a hot spare isn't necessary.

If you have a spare 4th drive I would mount it in an external enclosure and use it to backup your most important files.
!