# Possible to run 3 drives in RAID 0?



## DaUndeadRat

You can do RAID 0 with 2-4 drives, so ya, you could do 3 drives in a RAID 0 array.


----------



## DuckieHo

Actually you can have RAID0 with as many drives as you want... as long as it is more than 1 and you have a controller for them all. However, RAID0's MTBF is lowered with the addition of each HD. Don't forget failure of one drive means total loss of data in all drives with RAID0.


----------



## stargate125645

The drives don't have to be identical sizes, either. It will just make the smallest size drive as the size of all the drives in the array.


----------



## DuckieHo

Quote:


Originally Posted by *stargate125645* 
The drives don't have to be identical sizes, either. It will just make the smallest size drive as the size of all the drives in the array.

And the performance all the HDs will be limited by the worst HD.

Due to performance and size hit, it is recommended running identical drivers based on economics.


----------



## johnsrg

I'm building a system for a co-worker and he wants to save money and I thought of trying 3 WD160AAJS ($54.00 at Newegg) in a RAID 0 array rather than two 74gig Raptors. I'm thinking the 3 drives will be as fast if not faster than the two Raptors and the savings is substantial.


----------



## dannyyboii

Yes you can. For optimal performance, you should get 3 identical HDDs.


----------



## johnsrg

Been reviewing Tom's Hardware charts and the WD1600AAJS is a zippy little drive for only $54.00 bucks! So three or 4 in Raid 0 should be smokin fast.

http://www23.tomshardware.com/storag...2=675&chart=33


----------



## jacobdrw

Does it get faster as you add additional drives? or are 2 just as fast 3?


----------



## jacobdrw

bump


----------



## mcogan10

more drives = more performance


----------



## DuckieHo

Quote:


Originally Posted by *mcogan10* 
more drives = more performance

Diminishing returns though...

Add one HD, get a theortical 100% I/O gain but double risk.
Add another HD, get a theortical 50% further gain but triple risk.
Add another HD, get a theortical 25% further gain but quadruple risk.
Add another HD, get a theortical 20% further gain... ect


----------



## jNSKkK

You should get more speed from the more drives, but as Duckie said, it doesn't follow any logical order. Decreases with each drive you add.

Three should be alright though - Make sure you have a backup drive, just incase.


----------



## mcogan10

yes...raid 0's pitfall is the increased risk of drive failure


----------



## jacobdrw

thanks, but it is cool i put my documents on a seperate hd


----------



## DuckieHo

Quote:


Originally Posted by *jacobdrw* 
thanks, but it is cool i put my documents on a seperate hd

Not good enough for important documents. You may want to keep your docs on the RAID and run some type of backup to the seperate HD now. Hard drives *will* fail so make sure the only copy of your important stuff is on only one HD.


----------



## ENTERPRISE

Just some Info that may help at some point : http://en.wikipedia.org/wiki/RAID


----------



## MuniDude

So are you saying if I buy two 7500RPM drives and put them into RAID 0 it will mean the speed of the Raid setup is double or 15,000?


----------



## Marlaman

Quote:


Originally Posted by *MuniDude* 
So are you saying if I buy two 7500RPM drives and put them into RAID 0 it will mean the speed of the Raid setup is double or 15,000?

old thread bumper









the transfer speed will roughly be double depending on your raid controller-cheaper & onboard controllers will have less data throughput while higher end cards will bring you closer to "double" performance of a single drive.

It's definetly nice and speedy, even with a cheaper controller you get some pretty decent speed on your rig and loading times.

--remember hard drives are the botteneck in today's computers.

**hey Duckie i didn't say anything too ******ed did i?


----------



## DuckieHo

Quote:


Originally Posted by *MuniDude* 
So are you saying if I buy two 7500RPM drives and put them into RAID 0 it will mean the speed of the Raid setup is double or 15,000?

No...

First, it is 7200RPMs.








Second, you don't add the HD speeds... that would be like calling a 2.6GHz quad-core a 10.4GHz CPU....

What happens is if you have two 100MB/s HD... in RAID0, they will run at 200MB/s (in a perfect world). In the real-world, you should get 160-200MB/s. If you added another 100MB/s HD, you would get 200-300MB/s


----------



## D.J.S.

So get 3 drives and do 0+1 , I mean who does 0 without 1 unless you WANT to loose everything someday.


----------



## DuckieHo

Quote:


Originally Posted by *D.J.S.* 
So get 3 drives and do 0+1 , I mean who does 0 without 1 unless you WANT to loose everything someday.

You need at least 4 and even number of HDs for RAID0+1... you end up with n/2 space.

Many people do RAID0 with more than 2HDs....


----------



## MuniDude

Alright thanks for the clarification. My 7500 example was hypothetical so give me a little credit. My last question is about a RAID controller. What exactly is it as in is it a separate piece of hardware, built into the motherboard etc.. Am I good to go with my current setup?


----------



## DuckieHo

Quote:


Originally Posted by *MuniDude* 
Alright thanks for the clarification. My 7500 example was hypothetical so give me a little credit. My last question is about a RAID controller. What exactly is it as in is it a separate piece of hardware, built into the motherboard etc.. Am I good to go with my current setup?

Your motherboard has a host-based RAID controller onboard. You can use that.


----------



## MuniDude

I got it now. The read write capability is doubled. I was thinking the speed of the drives was doubled. I think you guys should all get paid because you are basically doing the job of a tech support guy at EVGA in your spare time. Hopefully I can add something soon to get my rep up to the coveted 2 spot.


----------



## The_Rocker

3 Drives in RAID 0 kick serious ass!


----------



## Massive17

Hey guys how come the addition of another drive increases the drive failure rate?


----------



## ljason8eg

Quote:


Originally Posted by *Massive17* 
Hey guys how come the addition of another drive increases the drive failure rate?

It doesn't increase the individual drive failure rate. It just makes it more likely that one drive in the array will fail, because you're using more drives.


----------



## Massive17

got it, thanks. So does anyone out there running RAID 0 has had one of their drives fail. I'm planning on running a RAID 0 with either two WD AALS or two Seagates


----------



## Slave One

Doesnt necessarily increase the drive failure rate of any of the drives... just increases you chances of one of those drives failing sooner or later and nuking all your data in the RAID.


----------



## Slave One

Quote:


Originally Posted by *Massive17* 
got it, thanks. So does anyone out there running RAID 0 has had one of their drives fail. I'm planning on running a RAID 0 with either two WD AALS or two Seagates

I would recommend the Seagates, but thats just personal preference, lol.

I can honestly say that I haven't had any of my seagate drives fail me, ever. I'll soon be setting up another RAID 0 soon, but this time on a couple of 15,000 RPM SAS drives!!

Just make sure you keep another drive installed seperate from the RAID, maybe even an external, and just keep up on your backups and you'll minimize your pain when one of your RAID drives fails.


----------



## Inuyasha1771

I'd stay away from Seagate for the moment, they had a bad batch of hard drives go out. I doubt you'd be affected, but WD seems like a much safer choice at this time.


----------



## Massive17

THanks for the advice, I was comparing the two:

View Post
*Seagate*

Cache 16MB
Average Seek Time 8.5ms
Average Write Time 10ms
Average Latency 4.16ms
*
WD Caviar Black*

Cache 32MB

# Average Seek Time: 8.9ms
# Average Write Time: 10.9ms
# Average Latency: 4.2ms

Seagates are slightly faster, but the WD have twice the cache size, does the cache size make a big difference or should I mainly look at speeds. Also are these two drives the best drives to run a RAID 0 with aside from the Raptors and the 15,000 RPM SAS's?

Quote:


Originally Posted by *Slave One* 
I would recommend the Seagates, but thats just personal preference, lol.

I can honestly say that I haven't had any of my seagate drives fail me, ever. I'll soon be setting up another RAID 0 soon, but this time on a couple of 15,000 RPM SAS drives!!

Just make sure you keep another drive installed seperate from the RAID, maybe even an external, and just keep up on your backups and you'll minimize your pain when one of your RAID drives fails.


----------



## MalVeauX

Heya,

Just to help a little with clarification when it comes to RAID and drive failure, misinformation can really scare people off. So when thinking of RAID, think of this little analogy:

When thinking of RAID and Drive Failure increases, it's the equivalent of you driving your Car on the street. If you only drove 3 times a week for 30 minutes and then suddenly increased your driving to 7 times a week for 2 hours each time, you're going to be more likely to be involved in an auto accident. Why? Because you drive more and longer. That's essentially what the Drive Failure comments are when talking about RAID. It has nothing to do with RAID in fact, it simply is because you're using more Hard Drives, and so mathematically, you're more likely to `have an accident.' Just like you're more likely to eventually be involved in a wreck if you drive a car every day for long periods of time.

RAID does not increase drive failure rate.
More Hard Drives simply gives more opportunity for one to fail.
And if one happened to be included in a RAID array, depending on your RAID level, it could result in the loss of the array.

If you have things you don't want to lose, RAID or no RAID, back them up off that system. If it's only documents, GMAIL them to yourself. Can't beat that. Or just burn them to a CD/DVD. If you have larger amounts of data to backup, seek real backup solutions _off_ the system.

Very best,


----------



## D.J.S.

Actually damn , is there no way to backup the 3 in 0 because of the need for a second stripe on 1
or couldnt 1 be just 1 drive ?? . I have never tried 3 0+1 personally.
usally its 2 0 + 2 1 and totally redundant


----------



## D.J.S.

Quote:


Originally Posted by *DuckieHo* 
You need at least 4 and even number of HDs for RAID0+1... you end up with n/2 space.

Many people do RAID0 with more than 2HDs....

You know alot more raid than I do , so youre saying 0+1
is not possible with 3(0)+1(1)

I really am curious now, would you need 6 x drives for this scenario?
3(0) x 3(1) 1 for each stripe to keep parity?


----------



## DuckieHo

Quote:


Originally Posted by *D.J.S.* 
You know alot more raid than I do , so youre saying 0+1
is not possible with 3(0)+1(1)

I really am curious now, would you need 6 x drives for this scenario?
3(0) x 3(1) 1 for each stripe to keep parity?

The drives have to be synchronized at all times.

If you even attempted 3xRAID0 + 1xRAID1, you would get the performance of the whatever array is slower and you would get the storage of whatever array is smaller. Basically, it would nullify any point of the RAID0.

RAID0+1 and RAID10 don't use parity. They use mirroring or exacty copies of sectors. RAID5 and 6 use parity... they derived sector based on the other sectors.

RAID0+1 and RAID10 use even number of drives and need at least 4 HDs. You get the redundency of RAID1 at the cost of half the drives and the performance of RAID0 of half the drives.


----------



## zhevra

Quote:


Originally Posted by *johnsrg* 
Does RAID 0 have to be configured evenly, like 2 drives, 4 drives? Or could I configure a RAID 0 array with 3 identical drives?









If i was you I'd raid two drives and use the other one has back up for my OS, and maybe some other files like videos and music..etc


----------



## DuckieHo

Quote:


Originally Posted by *zhevra* 
If i was you I'd raid two drives and use the other one has back up for my OS, and maybe some other files like videos and music..etc

Backing up the OS isn't as important as backing up your data. The OS is replacable, your data is not (easily).


----------



## zhevra

Quote:


Originally Posted by *DuckieHo* 
Backing up the OS isn't as important as backing up your data. The OS is replacable, your data is not (easily).

I was just giving an example of what he could do sir : )


----------



## D.J.S.

Aye so just straight up off array backup on seperate files. , thats pretty much how I have retained most of my stuff throughout the years anyhow .

So it is possible but , pointless .unless mabey you have ssd as your +1

hmm I just thought of something I have to try


----------



## Massive17

Quote:


Originally Posted by *MalVeauX* 
Heya,

Just to help a little with clarification when it comes to RAID and drive failure, misinformation can really scare people off. So when thinking of RAID, think of this little analogy:

When thinking of RAID and Drive Failure increases, it's the equivalent of you driving your Car on the street. If you only drove 3 times a week for 30 minutes and then suddenly increased your driving to 7 times a week for 2 hours each time, you're going to be more likely to be involved in an auto accident. Why? Because you drive more and longer. That's essentially what the Drive Failure comments are when talking about RAID. It has nothing to do with RAID in fact, it simply is because you're using more Hard Drives, and so mathematically, you're more likely to `have an accident.' Just like you're more likely to eventually be involved in a wreck if you drive a car every day for long periods of time.

RAID does not increase drive failure rate.
More Hard Drives simply gives more opportunity for one to fail.
And if one happened to be included in a RAID array, depending on your RAID level, it could result in the loss of the array.

If you have things you don't want to lose, RAID or no RAID, back them up off that system. If it's only documents, GMAIL them to yourself. Can't beat that. Or just burn them to a CD/DVD. If you have larger amounts of data to backup, seek real backup solutions _off_ the system.

Very best,

Thanks MalVeauX this is best explanation I have gotten about RAID 0 ever cause everyone kept saying that the failure rate doesn't go up but the chance of failure does, which would confuse the crap outta me. THanks!

- So does cache size matter when comparing hdd's or is the speed more important?


----------



## akmo

First off yes it is possible to run 3 Physical hardrives, as 1-Drive in Raid 0. The motherboard controllers will determine the max amount possible on your "array".

I did notice a performance boost, I was running 2-Drives in raid 0 then switch to 3-Drives in raid 0. The 150 Mb Floats up and down but is there
(Write times- are suppose to out perform SSD.) Seek times while important are only 1 second of your user experience.

I recommend The Sata Raid 0 w/ 3 Drives it is a noticable difference as oppose to 2-Drives @ 100Mb vs 150Mb

WD blacks TB are @ 80Mb
2 Intel SSD RAID are @ 180Mb

Screw the seek 1-sec is not important, In Raid - a program taking 1 minute is about 5 sec faster w/ each drive< From my experience.

Honestly if your running a quad core using words like multi task - GET A RAID SOMETHING:thumb:


----------



## beers

Yay, double thread necromancy.


----------



## akmo

BACK UP
Also Get an olds IDE Drive If you have dual IDE/SATA controllers and use it to backup data.

If you have designed your array most controllers allow you to add JBOD drive Just Basic Ordinary Drive LOL, And backup in windows.

I have lost new drives and ran some churning bearings for years, its the risk one takes using a single drive aswell as Raid 0

Also turn off Shadow copy as it fragments RAID drives (get an updated restore point and turn it off).

POWER MANEGMENT
I am running mine on an individual power supply eleminating power shock failure totally, 24 hour uptime.
This is done by shorting the PSU 4th and 7th Pins Green and black, Also balances power load if using 2-CD roms
4 hard drves and a case fan. An under powered drive can perform poorly, I notice a huge increase in the longevity of the HD.
Most hard drive onboard controller issues are power related problems. Consider it wont lose a write in a corrupt restart due to power failure!

CORRUPT FROM START
Churning bearings I might flip it for awhile or make sure drive is secure in bay, A shaking unsecure drive can corrupt allot of data.
NOTE CD-roms with High vibrations can write personal Versions of files only assesable/visible to the specific CD rom, Why would ur drive differ?

DEFRAG - FRAG
Turn off all Shadow volume service, back up services, SAVE A Restore point ... constant write utilized by the service fragmented my windows 7 30% on a fresh install and just updates. So a defrag was appart of my install . I did notice a slight less performance after patch fragment Like 10Mb Dropped off but windows runs so smooth out the box and degrades through time.


----------

