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stratex5
24-06-2012, 06:42 PM
Which RAID configuration would be best for 2x750GB 5400RPM HD?

Slankydudl
24-06-2012, 07:00 PM
it all depends on what you want. RAID 0 will just make them as like a single drive however if one fails then you lose everything. RAID 1 will write the same data too both disks.

icow
24-06-2012, 08:04 PM
^ This

stratex5
24-06-2012, 08:15 PM
Ok, thanks:)

Slankydudl
24-06-2012, 08:26 PM
and raid 0 increases your read speed i think

1101
25-06-2012, 11:46 AM
5400?? really ??
:-)
There was a thread a while back that mentioned some HD's are NOT recommended for Raid config's.

Chilling_Silence
25-06-2012, 12:57 PM
Most technically aren't, but you can still do it.

Iantech
25-06-2012, 01:38 PM
Striping the data (Raid 0) can give some small increase, sometimes used for things such as video editing where the user can use the huge capacity of effectively stitching 2 drives to make one large one, but yeah, the failure rate is also doubled as mentioned. Raid 1 (mirroring), while it prevents errors (or should I say "can help prevent errors"), it decreases data speed which is not recommended on a gaming pc. You also need good raid software, not having drivers etc up-to-date can and will cause it to crash and can take hours to re-mirror the drives again which can be a painful inconvenience. I had mirrored drives throughout the quakes, it served its purpose well, but really, unless you are running a network server or such, there is really no need for it or benefit from doing it. Most common retail drives are not recommended for RAID and proper raid drives are expensive. You can still do it with a normal drive as Chill said, but I would stay away from any "green" drives.

Chilling_Silence
25-06-2012, 02:13 PM
Most common retail drives are not recommended for RAID and proper raid drives are expensive. You can still do it with a normal drive as Chill said, but I would stay away from any "green" drives.

Green / Blue ... Even "Black" is still not *quite* ideal, due to a few reasons, but the Black drives were better than the others to say the least.

Most home users are better off just backing up rather than running a RAID array. What happens if the machine is caught in a fire? Theft? RAID won't prevent that, but backups which you can take offsite will!

Iantech
25-06-2012, 02:24 PM
100% agree, I would only (and have only) used 'black', run pretty stable for the most part. A backup you can take offsite is a much cheaper way to go :).

dugimodo
25-06-2012, 03:03 PM
RAID is not really for the average home user, more the coporate/ enterprise type enviroment where a drive failure and/ or performance is critical. Onboard RAID controllers are fairly basic and still do a lot in software and proper hardware RAID controllers cost more than a cheap computer.

Also RAID arrays are tied to the controller, you can't simply move a RAID array between machines with different RAID controllers without rebuilding it from scratch. Windows software RAID might avoid this but it also loads the system up a bit and doesn't perform as well.
Mirroring protects you from a sinlge drive failure but is not a backup, if you get a virus or a corrupt file or delete something by accident etc it'll screw up both copies.

A lot of gamers went for RAID 0 and fast drives for performance, but honestly games don't benefit from it much except in load times and now we have SSD's which are much better without using RAID.

So basically I agree with the others, don't bother with RAID and backup anything important to a seperate drive.

As to the dislike for 5400RPM and green drives, I agree they are not good for RAID but if you look at the performance figures for a 2TB WD green for example and compare it to a Blue or Black version you'll see it's actually very close and will even outperform the smaller 1TB versions of the 7200RPM drives due to higher data density. For storage drives which is what they are designed for they are very good, and in a pinch they do the job as a boot drive acceptably too.

Slankydudl
25-06-2012, 05:36 PM
So why exactly are consumer drives not ideal for RAID?

Alex B
25-06-2012, 11:56 PM
Raid should never be considered a replacement for backups.

WarNox
26-06-2012, 09:32 AM
Even HP uses consumer spec drives in their low end servers which are all RAIDed. The only thing with using RAID in home machines is that it will most likely be done with a shitty controller or software based and that is unreliable.

dugimodo
26-06-2012, 09:55 AM
Consumer grade drives will retry on a read error for quite a while before giving up, RAID controllers will sometimes see this delay as a faulty drive and drop it out of the array. If you google WD green RAID problems you will see a lot of people have this issue with them. Raid edition drives cost significantly more and are designed to avoid this and to run reliably 24/7.

you can RAID with consumer grade drives, it's just more prone to problems.

Chilling_Silence
26-06-2012, 10:24 AM
Yeah as dugimodo said, it's only an issue once it fails. Usually you do RAID because you want the better uptime (As mentioned, RAID is no substitute for backups), yet when you run into a drive failure it brings the whole machine usually to a complete standstill.

Slankydudl
26-06-2012, 05:29 PM
Okay that is interesting.

Chilling_Silence
26-06-2012, 05:47 PM
So lets say you put a WD Blue drive in a production server. For example, you've done a RAID1 (Mirroring) with 2x 1TB drives WD Blue drives, keeping the total available space at 1GB.
One of those drives fails

There's a pretty damn good chance you've just fubar'd the whole server until you replace the HDD and let it rebuild the whole damn RAID array. That's not a quick process.

If you use the Black, then there's a good chance it'll carry on working happily even rebuilding the RAID array in the background, maintaining the uptime of the server.


This is why backups are better than a RAID for most consumers, because the RAID is redundant.

Slankydudl
26-06-2012, 06:37 PM
So why does a black work like that when a blue doesnt?

Chilling_Silence
26-06-2012, 07:06 PM
The way that they handle errors. A home / consumer is more likely to want to try to re-read / re-write the data.

Black isn't even totally ideal, there was still something it didn't do quite right vs the Enterprise, but it was pretty damn close.

I looked in to it a while back. Have mostly forgotten since ...