Raid Question: Will different speed HDs work together?

[Edge]

Hi. I'm new to putting together RAID systems (though I'm on my 3rd home-made computer), and one of the things that I've been wondering is if I can RAID my 60 gig Western Digital 7200 RPM drive with my 5400 drive of the same company and size. I've checked around on forums and webpages but I couldn't find any answers.

I know you can't use different sized HDs for RAID, but would there be any problems with hooking different-speeded HDs together (other then the slower drive bottlenecking the configuration, of course). Thanks for any help you can give me.

[LORD-eX-Bu]

yes it would, but it would not work very well at all. In your case I would suggest you just set up your 7200 RPM drive as your IDE Primary Master and set your 5400 RPM drive as secondary master.;)

[Edge]

Hmm...yeah I was thinking about that...but I'd prefer having the raid set up (if for no other reason then just to say I have a raid set up:) ). would it at least be a bit faster then the 7200 RPM drive if I had them Raided? I mean granted it would be like having 2 5400 RPM drives, minus probably 400 for having the extra data redirection etc. through the motherboard, but that would still be a decent %30 or so increase over the 7200. And also, I'd prefer having just "1" harddrive, I always end up filling one drive first otherwise:)

[zsynth]

You can use hd's of different sizes, but loose some capacity, size wise. Let's say you hooked up an 80gig and a 40 gig, well it would only come out as a 80 gig raid array.
You can try to use different brand's of hd's but, it's a toss up if it will work at all, let alone reliably. Same thing with different types of hd's. A 7200rpm and a 5400- may work, reliably? Probably not.
The bad part of raid is loosing a stripe, and that can easily happen with perfectly matched hd's. I know, it happened twice to me with 2 matching 40 gig Maxtor's. I gave up on raid, don't need it. The new hd's with 8 meg cache is more than fast enough for me, and a heck of a lot more reliable. The only time you notice ANY difference with raid, is when you load a program with humungous amounts of data, such as my old F-4 Falcon game that had TONS of textures and scenery to load, or if you do a lot of video editing, or such. I used raid for a about a year, but without the reliablity, I'm happier without it. To utilize the fastest speed benefit of a raid setup, you must use raid-0. However, raid-0 is the most volital, and once you loose a stripe, you start all over again, setting it all up. Not worth the hassle for me.

AbitKR7A133-raid XP2100
Antec412 PSU Win98se
768megs PC2100(micron) (256meg ram drive)
LiteOn 48x24x48
AOpen DVD
(1) WD 80gig w\8meg buf
(3) 40gig Maxtor's ATA 133
Leadtek TI4400
TB Santa Cruz
Hauppauge TV card
D-link NIC

[Edge]

Hmm...well OK then maybe I'll give up on it. Just one quick question: what do you mean by loosing a "Stripe"? I'm new to raids so I'm kinda clueless. And if it would improve stability, I could actually switch my 7200 with my friends 5400 (which I KNOW is the exact same drive as mine becuase we got them togeter), but if you really think it won't make that big of difference then I'll just give up on it.

BTW, I actually do a lot a video editing, and 3d animation, and other big read/write things, so would I really notice the difference? Oh, and just how fast is that 8mb cache version compaired to a 2 meg? Mainly I'm looking at game load times and such, so as an example if a game takes 20 seconds to load on a regular 5400 RPM HD how much REALISTIC time would it cut off (I'm not a fan of synthetic benchmarks).

[zsynth]

Here's some raid links you can read up on to try and help you:
http://www.uni-mainz.de/~neuffer/scsi/what_is_raid.html

http://www.pcguide.com/ref/hdd/perf/raid/concepts/genStriping-c.html

http://www.tomshardware.com/storage/20000329/fastrak66-01.html

http://www.creativecow.net/articles/lindeboom_ron/how_raid_works/

Falcon 4, with the high rez scenery, used to take a long time to load (approx 1.5 minutes). With raid-0, it cut loading time to almost half. You will hardly notice any difference with a normal program or game. If you are doing a lot of editing with videos of very large size, than raid is worth the time saving. Ocasional editing, small or medium size clips, not worth the hassle (in MHO).
The 8 meg buffer hd is noticably faster than a reg 2 meg buffered drive, but were talking microseconds. If you can get a 8 meg buffered drive cheaper, get it (got my 80 gig WD for $89 - had a sale + $40 rebate)

[Edge]

The 8 meg buffer hd is noticably faster than a reg 2 meg buffered drive, but were talking microseconds.

Hmm, well I wouldn't call microseconds "noticably faster", I was looking for more along the lines of "cuts down %10" or "cuts in half" or something. Did anyone actually run any benchmarks to direcly compair an 8mb to a 2mb buffer drive? I didn't see any at anandtech or tom's hardware.

oh and thanks a bunch for the links, zsynth. If I had known about those before I might not have had to post here and waste all your time :D

Thanks again, I've learned a lot here.

[zsynth]

It's never a waist of time helping someone. I just ran HD Tach on my hd's. Here's what I got:

WD w\8meg 7200
Random Access Time 9.1 ms
Read speed average 48388.1 Kps

Maxtor 7200rpm 40 gig
Random Access Time 9.4 ms
Read speed average 36868.8 Kps

[LORD-eX-Bu]

Originally posted by zsynth
It's never a waist of time helping someone.

Good man.;)

[zsynth]

Here's a comparison I found for my hard drive vs others:

Western Digital Caviar WD800JB
(at bottom of articles listing)
http://www.storagereview.com/


P.S. Thank you sir! ([eNv]-LORD-eX-Bu)