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I am buying a desktop from Dell, they have an option 2 x 500GB 7200 RPM 2.5" SATA Hard Drive with Raid 0. I Googled about Raid 0 and found that it provides best performance.

But I am confused about disk space I will get. If I choose 2 x 500GB with Raid 0 then what disk space I will get 500 GB or 1 TB ?

Another question is: which will be better Raid 0 or Raid 1 ? I need good speed and performance but at the same time I don't want my system to be crashed.

Please check and advise, which one will be better and what disk space I will get.

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marked as duplicate by Nifle, Ƭᴇcʜιᴇ007, Sathya Feb 13 '13 at 13:37

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.


RAID 0 stripes your data across both disks. This means that every file is read from 2 places at once, giving significantly higher speed. Also, you get essentially the sum of the two disks ' space (so around 1 TB in that example) However, this comes at a cost - because the file is split across both disks, you're completely hosed if one breaks. In a normal two-disk setup, one disk can break and you can still recover data off the other; with RAID 0, it becomes very hard to recover ANYTHING if one disk has an issue. There is no redundancy.

RAID 1 is the simplest "real RAID". It is effectively mirrored disks, so you would just get 500 GB in your example. However, a RAID 1 system can still operate if one disk fails (in fact, it won't even shut off - it will just continue running like normal).

Which one is better depends on priorities. If you don't want to lose data, avoid RAID 0. If you want performance above reliability, RAID 0 can be a nice choice.

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What are the chances of failure with Raid 0, I want to use this system for managing remote servers and doing web development stuff. It will also run heavy software such as Dreamwaver, VS.NET, Phothosp etc. So should I go and spend money with Raid 0, or just buy normal 1TB 7200 RPM 3.5" SATA Hard Drive? – Prashant Feb 13 '13 at 11:52
For what the RAID levels are and what they do, please see this post on our sister SE site.… As to what is best for you is only something you and your purse can decide. RAID 0 for Pure read and write performance, more risks and daily backups can work quite well. RAID1 (mirror) is faster on reading and safer, but you loose half the space for a spare copy. And then there is the option you did not mention: A SSD (very fast but expensive) and a regular HDD. – Hennes Feb 13 '13 at 12:16
@Prashant - What does it matter what the chances of failure are? You should have the same type of backups no matter what you decide upon. Furthermore the chance of failure can be calculated by knowing the difference between says RAID 0 and RAID 1. You really to select a RAID that provides data integrity and data duplication. This why you know the integrity of the system is fine and if a single hdd fails you have the data duplicated on every disk in the RAID. All of this is easily researched.... – Ramhound Feb 13 '13 at 13:18

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