does raid have to be 2 of the same drive?

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mikelz85

[H]ard|Gawd
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I'd have posted this elsewhere, but I wasn't sure where, and I guess I feel more at home here.

Here's the short part: Can I use 2 drives of different models to run RAID (same size, same interface), or must they be the same hard drive? Are there performance hits? Compatibility issues? I have ordered 2 drives, and one doesn't work (newegg only offering RMA for refund)

Here's the story:
I recently ordered 2 seagate drives from newegg.com, both were identical refurbs of the same model. One of them doesn't work, and I've gotten an RMA from newegg for a refund (my original request was for another drive, but they said only a refund). Now I'm left with one working SATA 80gb SATA drive, which I have also requested a refund without restocking fee/shipping costs (essentially another RMA) for, due to the fact that I bought them as a pair, the order wasn't completed as specified (2 working drives), and I even passed over a less expensive drive due to the fact that there was only 1. Now if newegg won't do the RMA, or I don't need to (if there is no big deal running the same size drive of a different model, both SATA, I'll buy a another 80gb seagate SATA drive, but it's a different model) it'd be nice to know, as I'd hate to be stuck waiting around for another one of these drives to pop up on the refurb section (it could take months, and I might end buying my old one back by then :rolleyes: ).
 
If it does work, then I would hope it would be at least as fast as the slowest drive, unless the unmatched speeds result in serious timing issues.
 
My understanding is that if both drives are of the same size (ie: 80gb's or whatever), same speed (7200rpm etc), both sata/ide, both ncq/sata 150 etc, both have the same amount of memory cache 2mb/8mb/16mb, then their should be no compatibility problems even if they are from different manufacturers.

Say a seagate and a western digital ......I think it's more ideal to get 2 of the same drive to see maximum performance but I don't think you'll see a huge difference as long as the specs above are identical......at least this is my understanding but someone could prove me wrong as I'm not the knower of all things on hardware but I do read a lot :)
 
well if that were the case, there is a similar seagate HD, not sure how it differs, same size, both sata, both barracuda, but it is cheaper by $10 than the one i bought.
 
I agree with AOM. It is probably better to go with 2 of the same drives to avoid the hassel. I can imagine if you had stripping going on with a 40gb and a 80gb drive. Needless to say, it wouldn't be very pretty after the 40 is filled.
 
If you're setting up RAID 0 then you can use any size drives from any manufacturer. If you're setting up RAID 1, 1+0, or 5 then you'll need identical sized drives. Some RAID controllers will allow the use of differing sized drives for a non-RAID 0 setup, but all of the larger drives will be partitioned to match the size of the smallest drive in the array.
 
my question is if it is worth the hassel to get a full refund and wait around until 2 drives come along at that price (of the same make), which might be a few weeks (no big deal to me), or is the performance difference of a similar make (same cache, same line, same size) along with my current drive going to be neglible?
 
Contrary to popular belief, a RAID setup does not provide astoundingly better performance. I'll use RAID 0 (striping) as an example.

Drive 1 = 120GB. Drive 2 = 80GB. Drive 3 = 160GB.

RAID 0 with all 3 drives = 360GB.

The reason why there is a bit of a performace gain is because each drive's cache is being used almost simultaneously. 8MB x 3 = 24MB. A RAID controller stripes drives similar to what Windows can do without a RAID controller anyway (if striping is used on multiple partitions in the Drive Management console built in to Windows), but think of the RAID controller treating it's drive stripe like a dynamic drive volume, but hardware based (RAID controller BIOS) instead of software based (Windows dynamic disk access).
 
the benchmarks I've seen show pretty decent boosts, I meant raid 0 btw, sorry if there was some confusion.
 
Would you be so kind as to provide links to those reviews? I would be more than happy to check them out and give some insight to performance benefits if needed. Thanks
 
DejaWiz said:
Contrary to popular belief, a RAID setup does not provide astoundingly better performance. I'll use RAID 0 (striping) as an example.

Drive 1 = 120GB. Drive 2 = 80GB. Drive 3 = 160GB.

RAID 0 with all 3 drives = 360GB.

The reason why there is a bit of a performace gain is because each drive's cache is being used almost simultaneously. 8MB x 3 = 24MB. A RAID controller stripes drives similar to what Windows can do without a RAID controller anyway (if striping is used on multiple partitions in the Drive Management console built in to Windows), but think of the RAID controller treating it's drive stripe like a dynamic drive volume, but hardware based (RAID controller BIOS) instead of software based (Windows dynamic disk access).
Click to expand...

are you sure it makes a 360gb array? i thought raid 0 could only function with a distributed stripe so the smallest drive x number of drives determines array size. that would make the array 240gb (80x3)
 
Ya know, I did some deeper digging into RAID types. What I was describing wasn't RAID 0, it was JBOD. I was confused due to the fact that both JBOD and RAID 0 really aren't considered "RAID" configurations mainly due to the spanning or striping. Forgive my confusion and providing inaccurate explanations. Sorry, didn't intend to make an oopsie like this! I did some studying up on RAID types not long ago, and there certainly are quite a few out there, hence my apparent confusion.


RAID 0 can use multiple sized hard drives, but all drives will match size to the smallest drive size for uniformity. JBOD (Just a Bunch Of Disks) on the other hand, can span a volume over multiple drives, inclusing those on differing controller types (SATA + PATA, for instance).
 
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