2x RAID0 Velociraptors or 3x Samsung F1 drives?

Stonedofmoo

Stonedofmoo

Stonedofmoo

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I'm struggling with this one. I want a fast system array to replace my aging 74gig Raptors in RAID 0.

The new 150gig Velociraptors have been announced and I can make a 300Gb array for the cost of £250. It will be very fast in every way, shape and form, use little power and generate little heat... but its expensive.

However what I also have to consider is for £112 I could equally have 3x Samsung 320gig F1 drives. In RAID 0 they would be faster than the raptors in sheer data transfer rates. On the negative they would use more power, generate more heat, have slower access times and statistically increase the chance of that array failing (not that I'm bothered too much as data is stored on other drives.

So 2x 150Gb VRaptors £250
or
3x 320gig Samsung F1 - £112

Factoring in all considerations including power drain as my PC is on an awful lot... which would you choose?
 
Raiding HDD's together makes the Seek slower, so adding 3x non Raptors that already have a slower Seek together will make it even slower.

The Raptors have a very fast Seek to start with so in Raid will be about the same as a normal fast HDD's Seek.

Do you really need 660GB inside your PC case at any one time ? (I use external for backup and stuff that ain't used much).
 
personally i'm moving away from raid 0 (selling my 74 gb raptors), just going to use single drives from now on, they're so big now it's a lot of data to lose if something did go wrong..

plus with 100mb/s write speeds, the newer drives are hardly slow :)

-ooh, just re-read your post, 2x 150's is decent... (not too big either if you get what i mean)


both will rock in performance..
 
The 150GB velociraptor hasn't been OFFICIALLY announced yet, nor are prices out for those?

If you want 3 drives in raid0 onboard sata raid wont really be enough you'll need a hardware raid card which would be £90+.

I'd get 2 * 150GB velociraptors.

Just noticed a place selling samsung f1 320gb HD322HJ for £38, slackworth, go add these NOWWWWWWWWWWWWW!!!!!!!!!!!!
 
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The difference in heat and power is negligible, about 10w difference I believe? The transfer rate advantage of Raptors isn't very big either, it's just the seek time where they excel.
What do you do that requires high transfer rates? It gives hardly any advantage most of the time so if you don't have a real need for it then look at getting a single SSD which has good STR's and amazing seeks.
 
interestingggggggggggg, when were those new velociraptor 74gb + 150gb drives added to pre-order, dont remember seeing those in the overclockers.co.uk/news section. £124 aint too bad really. the 74gb raptor is a bit of a gimmick as it will be a lot slower due to less data per square inch compared to the single platter 150GB velociraptor.
 
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ken1307 said:
how about RAID0 with 2 of this : http://www.overclockers.co.uk/showp...SATA-II Solid State Hard Drive (OCZSSD2-1C32G) ? :D
Click to expand...

SSD's don't interest me. If you buy one now the technoligy is moving so fast the model you buy will be made redundant in 6 months or less, plus the cost per Gb isn't reasonable.

I don't need much space, 200-300Gig is fine as I only use it for a system drive anyhow but I WOULD like an array that is quieter than the existing 74gig Raptors. I watch a lot of movies in my room ,and the constant clicking they make as Vista does stuff can be irritating.

I'm quite tempted by the 150gig raptors and theres no need for a 'hardware' RAID card as the Intel onboard RAID controller works just as well as this technoligy level, and it doesn't get hamstrung by the BUS those hardware cards are connected too.

Hmm, still no definite answers but I'm taking in your replies.
 
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Yes 2 of those 150gb raptors would be nice. But for 3 * samsung f1 in raid0 onboard sata raid will be limited, just like with raid5, onboard raid5 speeds are very poor. The velociraptors are supposed to be relatively quiet, atleast compared to the older 74/150gb raptors which i had which was noisy as hell. They will obviously be a lot louder than the samsung f1 drives, just depends on what matters more to you, money, speed, noise?

You could just get 2 * samsung f1 320GB for £75.
 
papertape.jpg

In RAID0 ;-)
 
helmutcheese said:
Common knowledge, wiki Raid 0 or such.
Click to expand...

Wiki says that the seek time of the RAID array will generally be the same, and in some circumstances faster:

Wikipedia said:
For reads and writes that are larger than the stripe size, such as copying files or video playback, the disks will be seeking to the same position on each disk, so the seek time of the array will be the same as that of a single drive. For reads and writes that are smaller than the stripe size, such as database access, the drives will be able to seek independently. If the sectors accessed are spread evenly between the two drives, the apparent seek time of the array will be half that of a single drive (assuming the disks in the array have identical access time characteristics)
Click to expand...
 
I was always taught in Raid0 it get higher, I know others here think the same.

I ain't a Raid expert, I install it and forget about it. :)

Remember wiki is wrote by a normal peep and can be wrong.



QUOTED :


" Seek times on RAID-0 are generally slower than for a single drive so for small
amounts of data, a single drive will be faster

After setting up two hard drives in raid 0 my average seek times went UP to 11ms from 8ms on a single drive

In testing with my Raptors, my seek times actually increased with a RAID0 setup "



" The disk is spinning. The "average access" (not seek time) is comprised of
the time taken to move the heads to the correct track (strictly the real seek
time) and the time taken for the disk to spin to a position such that the
sector that is required is under the heads. For a 10,000rpm disk (not the
fastest we can get nowadays but still quite fast) the time taken for a
complete revolution is 6ms. This means that the average time to find a
sector will be 3ms once the heads are on the correct cylinder.

If there is only one disk being used for a small write then the average time
will be 3ms. If there are four disks and their spindles are not synchronised
(I think that synchronised disks have not been manufactured for some time)
then the average time for the sector to be found on all disks will be greater
than 3ms, maybe close to 6ms. "



http://www.hardforum.com/showthread.php?t=887154


After reading all the above info and info they linked to I tend to agree.

I have ran my 2 Raptor X's in Non Raid and Raid0 for years and the Seek does increase in Raid0 in any Bench APP's like HD-Tach etc etc.
 
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I don't know much either other than what I read. The question was posted on Experts Exchange and the accepted 'Expert Answer' was as follows

The calculations above show the # of writes for a particular set of data, but don't address your question about latency. The latency is not a function of the number of drives, but of the rotational speed of the drives. The more drives you have, the faster the sustained transfer rate; but the seek time and rotational latency is the same whether you have one drive or ten.

With a large # of small files, the access time could be a notable factor in performance, since a faster set of drives would give you a several millisecond "head start" on data transfers ... and indeed may actually finish a transfer before slower drives would even start. In that case, you'd get appreciably better performance by using faster drives rather than more drives. Switching your drives to 10,000 rpm Raptors would be a much better performance improvement. Their average seek time of 4.5 ms is half of a typical 7200 rpm drive; and their rotational latency is 2.99ms vs. 4.2ms for a 7200 rpm drive => combined that's about a 5.7 ms/access advantage ==> enough time to transfer 1.37MB (at 80MB/s sustained rate x 3 drives x 5.7 ms) ... and that would be done BEFORE a set of 7200 rpm drives would even start transferring any data !!
Click to expand...

Certainly a eye opening answer.
 
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