#99694 - 16/06/2002 10:47
RAID Configuration
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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I'm thinking of setting up a small RAID 5 config in my new PC. I'm thinking 3 9.1GB drives. This, if I understand it correctly, would give me 18GB of storage and one drive for parity.
These are the drives I was thinking of getting, as to not hit my wallet too hard.
One question I have is: how will these specific drives compare to and IDE drive? At the moment I've got one 20GB 5400RPM and a 25GB 7200RPM, but IDE, although the second might be busted.
This setup will be for my OS drive, as I have a 100GB drive for files (which is almost filled!).
My other major question is: what card should I get for these things? I'm thinking cheap, here, but I want to get maximum throughput from these drives.
Any advice?
ps-one side question for RAM. what is ECC and is it better with or without?
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Matt
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#99695 - 16/06/2002 11:40
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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I'm thinking 3 9.1GB drives. This, if I understand it correctly, would give me 18GB of storage and one drive for parity
Correct. Though the parity is spread across the 3 drives.
These are the drives I was thinking of getting, as to not hit my wallet too hard.
50 pin? Thats going to probably indicate those drives can only pull a maximum of 20mb/s, and probably closer to 10. My 30gb IDE can pull 27.2 real world.
Go with IDE RAID for a PC. IDE raid cards varry on price, any IDE card that can do Raid 5 will be around $200 minimum, but it will be a decent card. To get peformance with SCSI, it costs money. IDE for a PC use will be fine.
one side question for RAM. what is ECC and is it better with or without?
Depends. ECC is an error correcting scheme for memory, allowing simple failures to occur without impacting the machine. Normally a memory error crashes a machine instantly (OS typicially crashes it's self to protect data from furthur harm). ECC is used in almost all servers. As long as your motherboard supports it, and provides some warning when errors have been fixed, I'd say go for it. But if it can't notify you when errors occur, it's not very useful. ECC can generally give signs it's about to fail, and allow you to replace the module before it craps out completly and leavs you with odd blue screens or kernel panics.
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#99696 - 16/06/2002 13:08
Re: RAID Configuration
[Re: Dignan]
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Carpal Tunnel
Registered: 08/02/2002
Posts: 3411
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I'm with Drakino on this one...you'll get far more bang for your buck with IDE.
But I can't see why you want to place your OS on RAID5, but not your data? OS's are easily replaceable...
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Mk2a 60GB Blue. Serial 030102962
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#99697 - 16/06/2002 13:12
Re: RAID Configuration
[Re: genixia]
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enthusiast
Registered: 07/01/2002
Posts: 339
Loc: Squamish, BC
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Maybe he uses his computer for business, and any unscheduled downtime of his OS would be a big issue, but the loss of his MP3 collection would be a minor problem.
This of course assumes he's going to store his *important* files on the RAID setup, but with 18gb available space, I'd imagine he'd not have a problem doing this...
A.
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#99698 - 16/06/2002 14:51
Re: RAID Configuration
[Re: drakino]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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Thanks so much for the response! You've helped a lot.
I wasn't thinking IDE RAID because I wasn't under the impression that it was very good. But if you think that it's a good idea, I'm perfectly willing to put my money to better use Plus, I'm getting a SOYO Dragon Ultra mobo, and it has IDE RAID built in, so that would be a plus, right?
My reasoning for a RAID on the OS? I was under the impression that it was faster, and I'd get better performance from it. Sure, I'd love to have my data much more secure, and I might go that route. But with your new suggestions, I might have to think up a whole different route I want to go in
My ideal (and I'm sure, the general ideal) would be fast running programs and OS, plus secure data files. I also want to keep my 100GB drive intact with all its files still on there.
Do you think I'd be able to run 2 RAIDs on the same system off the mobo?
*edit* I looked at the mobo's spec page and it says:
R: Embedded Hipoint IDE-RAID chip, providing ATA-133 IDE-RAID 0,1,0+1
Are those the configs it supports? Can someone explain those to me?
Edited by DiGNAN17 (16/06/2002 15:02)
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Matt
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#99699 - 16/06/2002 15:37
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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RAID can produce some speed advantage over normal disks. Putting your OS on the RAID might speed bootup a bit, but a good chunk of time wasted by the OS is waiting on devices to start, or trying to do a quick new hardware scan. Programs will load quicker off a RAID device, but having more memory is also critical for decent program preformance.
The IDE RAID found on motherboards usually does only support the basic 0, 1, and 0+1. Check out http://anandtech.com/storage/showdoc.html?i=1491 for info on these, and some tests from last year of some IDE cards. Notice the ones that do RAID 5 are much more complex, due to the necessary chips to do the processing of parity. High end SCSI controllers that do 2 types of parity usually have something like a PowerPC chip on them to help out.
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#99700 - 16/06/2002 15:48
Re: RAID Configuration
[Re: Dignan]
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enthusiast
Registered: 07/01/2002
Posts: 339
Loc: Squamish, BC
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Yeah, the motherboards only support basic RAID, and are generally not very good quality - the main reason for implementing it is to give you 8 IDE devices instead of 4 connectable as standard. (Note, only 4 of the 8 devices can be set up for RAID)
If you're looking for speed alone, there's little point in going for RAID 5, which includes redundancy as well. You'll get optimum performance (at least on low-cost RAID cards) using what's known as RAID 0, which is simple disk striping, where a file is stored across more than one disk and so can be read from two (or more) disks simultaneously.
The motherboard options you have are:
RAID 0, which is up to 4 disks of striping, giving you theoretically 4 times the performance of a single drive (although realistically nothing near this). RAID 0 has no redundancy - any failure will mean virtually all data is lost. In this system, you get the full storage capacity (4 times the single disk size)
RAID 1, which is up to 4 disks of mirroring, gives you only the storage capacity of the smallest disk installed. Each file is written to all the disks at once, potentially allowing up to three failures (if you have 4 drives in this format) before any data loss. A decent RAID 1 system will allow you to swap in a new disk, and will then rebuild this disk so you retain maximum fault tolerance.
A RAID 0+1 system is, as it suggests, a combination of the two - in this case, 4 drives, with files striped (see RAID 0) across two disks, and mirrored across the other two. This gives you up to twice the performance of a single drive (again, theoretically), whilst meaning you can have up to 2 disk failures (although not any two, either the two main or the two backup disks) before data loss. In this case, you get twice the capacity of a single disk, or half the capacity of the total system, available for use.
If you want to stick with the Mobo RAID support, and have faster file access plus some redundancy, RAID 0+1 is probably the way to go - however, you do need 4 disks, preferably all the same size, to go down this route.
As you've gathered, this setup is cheaper in interface cost than a dedicated RAID controller, but more expensive in disk storage terms - with a RAID 5 controller, you could use the 4 disks in your RAID 0+1 system, to get 3 times the single disk size, up to 3 times transfer speed of a single disk, and still have the ability for any disk to fail.
HTH,
A.
*edit: gah, beaten to it!*
Edited by snoopstah (16/06/2002 15:49)
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#99701 - 16/06/2002 16:20
Re: RAID Configuration
[Re: snoopstah]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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Haha, thanks a lot you guys.
For the moment, I think I might try the onboard RAID. Later, with more money, I may god card-based, but for now I'll stick to the cheapest I can
Based on that, I have one more question: is it possible to run two RAID's on the same onboard system? Here is what I'm thinking:
1) buy a second 100GB drive, and use RAID 1, thereby keeping my DATA safer.
2a) buy a couple small, fast IDE drives and run a RAID 0 for the OS and programs. thereby getting a good speed advantage.
2b) forget about RAID for the OS and buy the fastest single drive I can find, for as you said, OS's are replaceable.
So as you may have figured, I'd try 1 and 2a or 2b. But I'm not sure how it works if you want two seperate systems running. Any idea how that would work? I would like to keep the OS and data seperate.
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Matt
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#99702 - 17/06/2002 06:52
Re: RAID Configuration
[Re: snoopstah]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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Any ideas on what the fastest single drive I should go for would be?
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Matt
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#99703 - 17/06/2002 08:07
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 20/05/2001
Posts: 2616
Loc: Bruges, Belgium
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The western Digital Caviar Special Edition series is hands down the fastest IDE disk out there. With it's 8Mb buffer it can archieve speeds that are equal to (slow) 10.000RPM SCSI harddisks in some tests.
It's very affordable too and is available in 80,100 and 120gb sizes. (see here)
I have one and I've been very impressed with it.
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Riocar 80gig S/N : 010101580 red Riocar 80gig (010102106) - backup
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#99704 - 17/06/2002 09:39
Re: RAID Configuration
[Re: BartDG]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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Yeah, that is an excellent drive. I'm sure thinking about that one. It goes for about $120-125 for OEM. Not too bad at all, considering my 25GB WD drive that I bought 2.5 years ago was $250. I also think they're the best drives around.
Plus, at Newegg, I can also get that OEM Win2K software that Rob showed me and I'll feel a little better about the software I'm running on my machine, if you know what I mean
Still, it's a lot of money. I'm going to have to think about this one...
----
Back ot the RAID topic: if I just have this two-drive system for a while and upgrade with another hard drive later, how easy is it to creat a RAID with an existing drive with all its data? How easy is it to isolate the other drive that won't be part of the RAID? For example, say I have that 80gig as my OS drive, my 100gig for my data, and I buy another 100gig drive. How easy will it be to make a 100GB RAID 1 with my data drive without losing that data, and also run my OS drive normally? And is it a software thing or a hardware? Remember, this will most likely be off the mobo.
Sorry for all the questions! You've all been so helpful!!
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Matt
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#99705 - 17/06/2002 10:01
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 20/12/1999
Posts: 31594
Loc: Seattle, WA
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I have only one recommendation regarding a RAID array (should you decide to get one):
COOL THOSE DRIVES.
When someone stacks several high-speed 3.5" disk drives in a PC case, they don't often realize how much heat they put out. You need air circulation around the drives because they'll heat each other up and the drives can fry if you're not careful. They even make little replacement 5" drive-bay cover plates that have little fans in them. If you don't have air going around the drives already, I'd recommend at least one of these faceplate-thingys on the middle of the three drives.
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#99706 - 17/06/2002 10:21
Re: RAID Configuration
[Re: tfabris]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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Actually, the case I'm getting will take care of that just fine, should i eventually go that direction. There's a 5 drive bay cage at the bottom directly behind 2 80mm fans. So at the moment, I'll have 2 drives, each a bay apart, and if I had 3 drives, they would still be a bay apart from each other. Cooling shouldn't be too bad.
I really just am not sure about those other aspects of the array. Cooling was certainly a concern, but I thought that might be enough. Do you think it will be?
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Matt
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#99707 - 17/06/2002 11:54
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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Back ot the RAID topic: if I just have this two-drive system for a while and upgrade with another hard drive later, how easy is it to creat a RAID with an existing drive with all its data? How easy is it to isolate the other drive that won't be part of the RAID?
It all depends on the particular RAID controller. The expensive SCSI ones I work with never allow a drive to sit attached to them without being in an array. It has to be at least a single drive RAID 0. They do allow expanding the array by adding new drives. Also, they allow RAID migration, thus going from a single RAID 0 setup to a RAID 1. But again, it all depends on your particular controller. If you have an idea of one, I recommend you go ask in the forms at www.storagereview.com , they seem pretty helpful and do talk about different RAID controllers.
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#99708 - 17/06/2002 12:21
Re: RAID Configuration
[Re: drakino]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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Hmm. that's not too good. Oh well, if I ever want to go with a RAID I could just buy a card, and still run the single hard drive off the mobo.
Oh, and I ordered the Western Digital SE drive. That should be so sweet.
I'm getting antsy waiting for about 10 packages to come into the office here AHHH!
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Matt
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#99709 - 17/06/2002 12:28
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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I'm getting antsy waiting for about 10 packages to come into the office here
My bank account is patiently waiting for me to buy my next system. I got the Plextor drive now, but everything else is on hold until my case/motherboard gets released. I'm getting so impatient, and buying the hard drive and such won't help.
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#99710 - 17/06/2002 13:18
Re: RAID Configuration
[Re: drakino]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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What case/mobo are you holding out for?
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Matt
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#99711 - 17/06/2002 13:42
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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What case/mobo are you holding out for?
http://www.viahardware.com/computex02sff_1.shtm
The Shuttle SS51. It's an evolution of the SS50 models, it adds some nice features like AGP and I believe USB 2 to an already awesome package. After getting a G4 Cube, I'm hooked on small form factor machines. And lucially, in the past year, standards have emerged. With this case and my LCD monitor, I'll be able to go to LAN parties, and only make one trip from the car.
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#99712 - 17/06/2002 13:50
Re: RAID Configuration
[Re: drakino]
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carpal tunnel
Registered: 20/12/1999
Posts: 31594
Loc: Seattle, WA
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Damn, now you've got me wanting one.
I'm set up for a single-trip-from-the-car LAN party, too, but I have a full size case and a full size 17" monitor. Adding the handles is what made them portable. So it's one trip, but it's a slow careful trip that makes me sore afterwards.
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#99713 - 17/06/2002 15:03
Re: RAID Configuration
[Re: tfabris]
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Pooh-Bah
Registered: 09/09/1999
Posts: 1721
Loc: San Jose, CA
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Does anyone have any suggestions on *external* ide hard drive enclosures for a RAID setup? Keyword: Cheap? I'm thinking something that lets me throw some hard disks in, then get a raid card, and somehow (?) hook the two of them up. My main hard drive with its XP boot partition is dying. I'm going to ghost it over to a new hard drive, but this raid talk has me interested.
Calvin
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#99714 - 17/06/2002 15:09
Re: RAID Configuration
[Re: eternalsun]
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carpal tunnel
Registered: 20/12/1999
Posts: 31594
Loc: Seattle, WA
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What you're looking for exists, but I don't think "cheap" enters into the equation.
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#99715 - 17/06/2002 15:18
Re: RAID Configuration
[Re: tfabris]
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enthusiast
Registered: 08/03/2001
Posts: 202
Loc: Denver, CO
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When I put up my RIAD box it will be a totally seperate machine in it's own box connected via Gigabit ethernet. It'll run nothing but Win2k for mapping. In looking, I found it's the best (and cheapest) way to do it.
Promise makes a 4 Drive and 8 Drive ATA External RAID solution, but it's WAY too expensive. I can build a Dualie Athlon Box WITH the 1.12TB Of space and a 3Ware Escalade 7850 for cheaper then I can get the 8 Drive Promise alone.
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- Damien
- Mk2a 24G Blue SN: 120001043
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#99716 - 17/06/2002 17:09
Re: RAID Configuration
[Re: xanatos]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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Win2K for mapping? Just run a stripped down Linux install with Samba, thus giving you a nice and easy to use web interface built in.
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#99717 - 17/06/2002 17:31
Re: RAID Configuration
[Re: drakino]
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enthusiast
Registered: 08/03/2001
Posts: 202
Loc: Denver, CO
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I like linux and all. But I don't trust myself enough with it. And the 48bit support in linux is kinda shotty right now. And the drivers for the 7850 have been tuned for win2k more.. *shrugs*
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- Damien
- Mk2a 24G Blue SN: 120001043
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#99718 - 17/06/2002 19:53
Re: RAID Configuration
[Re: Dignan]
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addict
Registered: 08/01/2002
Posts: 419
Loc: Minnesota
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I've had an MSI RAID board for about a year now, I'm so-so with it all. I was running a pair of IBM hard drives RAID 0 for speed, and about every month had to reformat because so much data was getting lost it slowly got to where it wouldn't even boot up.
I switched to a pair of WD 80's and ran it that way a few months with no problems at all.
Later I bought a pair of the 8MB 120's, and sold one of the 80's, which is where I'm at right now. Even though I finally ahd success running RAID, I ditched it all together.
Currently I have both 120's hooked up individually to the RAID channels. The remaining 80 is off the normal IDE channels, along with a high speed CD ROM, a burner, and a DVD player (so really all I'm doing is using the RAID channels simply to add more devices). The 80 itself has its ground wiresrun to a switch on the front of the box.
Last time I installed (many moons ago), I set one 120 to hold my O/S and all the programs I have installed. The other is just for MP3 and movie storage (nowhere near filled yet overall). The 80 is turned on once in a while just to make backups of things onto and then back off.
I have run my setups at RAID 0 and just normally - and even though the benchmarks showed about a half again performance boost, in real life I could tell no difference at all (partly from a tweaked Athlon 1.4 running ~1550 and a half gig of RAM perhaps). I couldn't rip a CD any faster, I couldn't load a game or the O/S any faster, and I barely could even transfer from disk to disk faster. I timed a ton of different things and eventually decided it made very little difference. Perhaps it's just due to what I use my PC for - when I need power, it seems to be CPU based needs and not hard drive needs.
So now I just use the RAID channels to have 6 instead of 4 devices. And with the 80 on the switch, I have a really reliable backup for home use in case something happens to the main drives.
Lots of babbling, hopefully some part of it was helpful.
BTW, glad you got a big drive, those you linked at the top were really poor in the size / dollars ratio, not to mention slow!
Edited by tracerbullet (17/06/2002 20:01)
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#99719 - 18/06/2002 05:30
Re: RAID Configuration
[Re: tracerbullet]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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Thanks for the help!
The thing is, I'm probably going with a RAID 1 now if at all. I now have that Caviar SE drive to give me good, uncomplicated speed, and if I do go with a RAID in the future, it'll be to make my data safer. I'm currently taking up about 98GB of my 100GB drive, and while 26GB of that is Dragonball Z episodes (;)), there's still alot of files that I'm going to want to save.
Do you think onboard RAID 1 would be as bad? It looks to me that there might be less room for errors like the ones you experienced, but I don't know. Besides, from what I gather from people here, it sounds like I'll need an IDE RAID card anyway if I want to run the single 80GB one seperately. Oh well, this is all down-the-road stuff.
Nice small case there, Drakino! I, on the other hand, am going the opposite way It should be coming in today, then I'll show you all what I got
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Matt
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#99720 - 18/06/2002 07:48
Re: RAID Configuration
[Re: drakino]
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carpal tunnel
Registered: 08/03/2000
Posts: 12338
Loc: Sterling, VA
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I think I now have the opposite case that you're waiting for, Drakino.
I am the proud new owner of a Lian-Li PC75 aluminum case. 15 bays 6x5.25, 3x3.5, 6x3.5 hidden. HUGE side window. 4 80mm fans included, spots for two more.
Yes, I'm insane. My only justification is that I've had a Dell for 3 years, so please take pitty on me.
"Dude, I'm gettin' rid of a Dell!"
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Matt
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#99721 - 18/06/2002 09:34
Re: RAID Configuration
[Re: Dignan]
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carpal tunnel
Registered: 08/06/1999
Posts: 7868
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I work around big machines all day with tons of fan noise, so I think thats one of the reasons I am going smaller at home. If I need a ton of storage, a server is always somewhere on the network that can have more drives added. And it's noise is isolated to the basement. Plus, all the LAN parties I attend (and some I don't sue to the hassle) will be easier with a tiny case.
As far as RAID 1, the onboard motherboard one should be fine. But, one big disadvantage I see is if it fails, and the motherboard is no longer made, finding a compatible solution to get your data back could be a problem.
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#99722 - 18/06/2002 10:25
Re: RAID Configuration
[Re: drakino]
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carpal tunnel
Registered: 19/01/2002
Posts: 3584
Loc: Columbus, OH
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But, one big disadvantage I see is if it fails, and the motherboard is no longer made, finding a compatible solution to get your data back could be a problem
Many of the boards use an onboard Promise RAID controller. In the event that it dies, you should be able to replace it with one of their PCI RAID controller cards and be back up in no time.
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~ John
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#99723 - 18/06/2002 10:35
Re: RAID Configuration
[Re: drakino]
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carpal tunnel
Registered: 13/07/2000
Posts: 4180
Loc: Cambridge, England
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But, one big disadvantage I see is if it fails, and the motherboard is no longer made, finding a compatible solution to get your data back could be a problem.
RAID is not an alternative to off-site backups, even for personal data. It just reduces the number of events that would cause a recourse to off-site backups.
Peter
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