# RAID 0 with two non matching hdds



## Snake05 (Apr 17, 2008)

Here is my situation.  I currently have my Seagate hooked up as my OS drive, and my Maxtor (both in specs) is sitting unused in my computer (mainly because videocard blocks my last SATA port).  Once that port is available, I want to set up a RAID 0 array with the two hdds.  I have a few questions about compatability though.  I know that since one is a 320 and the other is a 200, that the array will mirror the 200, but that is fine with me.  My main concern is the transfer speed of the two drives differs (Maxtor is 1.5 and Seagate is 3.0).  I do not believe that my Seagate is currently running at 3.0 (SATA 1 cable I believe), but I would like the array to run as fast as possible.  Correct me if I'm wrong, but won't this default the array to 1.5?  Would I see more of a difference from this, or if I hooked my current Seagate up with a SATA 2 cable and went to 3.0?  According to Vista's Performance Index, the current primary is rated to a 5.6, but I would like to improve that.  Any other setup suggestions?


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## newtekie1 (Apr 17, 2008)

There is no speed difference between SATA 1.5Gb/s and 3.0Gb/s.  There is no difference between the cables either, more than likely your seagate drive has the jumper set on the back of the driver to limit it to SATA 1.5Gb/s.  They ship the drives this way for some reason, probably to increase compatibility.


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## lemonadesoda (Apr 17, 2008)

FACT 1
If you want serious RAID0 performance, you really need a hardware caching controller. The onboard RAID chipsets are OK, but unless you are on a server chipset, I've never seen gains that are worth the cost and effort on a cheap mainboard. Its more of a "feature set" than genuine superb performance. The RAID is actually software-RAID and takes CPU cycles to manage.

FACT2
Often a new HDD will add more performance than trying to RAID older drives. The new super-high-density drives today are faster than raptor 10K drives in most benchmarks. (Sustained read rates)

FACT3
There is a BIG difference in burst speeds between SATA 150 and SATA 300. The bigger the cache of the HDD, the more the SATA 150 interface will bottleneck potential performance. Thats very noticeable with the new 32MB cache samsung F1 drives. I lose 50% "burst speed" performance with 150 over 300, and about 10% raw data sustained rates.

FACT4
Since 99% of current HDDs do not get have average sustained read rates >100MB, you are OK with SATA 150 as an in interface standard.  It will not be a major handicap. Just be aware that you dont get full value out of the HDD cache.

YOUR SITUATION
Predicting the speed improvement of the suggested RAID setup is difficult.

I would actually suggest a different route:
1. Fast HDD for system partition and swapfile
2. Slower HDD for your data and games directory

In this situation your drives can work independently... getting data off the games HDD while writing data to the swapfile etc.  You'd get better performance in most situations by having two independent drives. It also consumes a lot less power when the drives are "idle".

IMO, RAID 0 should only be considered for jobs like video-editting, where e.g. you have a OS HDD, then 2 RAID0 HDDs with your media files... or for database crunching. 

Most people who set up RAID 0 and have ALL their OS, data, games on the same RAID array dont tend to get better overall performance. Yes, then boot time is a bit quicker... and a map load is a bit quicker... but in practice, the gains are small %.

FACT5
RAID0 is MORE RISKY TO DATA LOSS than no RAID. Remember RAID does not mean safety of your data. Only when you have a dedundant drive is the data safer.


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## Snake05 (Apr 17, 2008)

I actually have 3 hdds, one of them I did not mention is my WD 750, which I use for my media, games, etc.  I have plenty of storage, and as of right now, I am not even using the Maxtor.  It can either sit there and not be used, or if this setup will give me even a slight increase of read or transfer times, then I'd like to do this.  If one goes out, oh well, I'll just settle for a normal SATA interface.


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## Scrizz (Apr 17, 2008)

lemonadesoda said:


> FACT5
> RAID0 is MORE RISKY TO DATA LOSS than no RAID. Remember RAID does not mean safety of your data. Only when you have a *dedundant* drive is the data safer.



So where can I find a dedundant drive  
If its safer than a *redundant* array I'm all for it.


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## lemonadesoda (Apr 17, 2008)

scrizz u spelling nazi


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## Snake05 (Apr 17, 2008)

So, the one real question here would be would I get better performance from a RAID 0 with these arrays than the Seagate along (assuming 3.0).


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## lemonadesoda (Apr 17, 2008)

The answer is:  the difference will be SO SMALL its not worth the effort of reformatting both drives, reinstalling OS, etc. etc.


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