Raid?

[mediaboy]

Just exactly what is RAID? Do you have to have RAID from the moment you build a computer, or is it something you can later add in? What happens if you can add it in... does it affect any current memory? Is RAID a worthwhile thing to get? Should I bother getting RAID on a AX78?

Me thinks it is compatible to some extent but unsure - guidance?

In case it matters:

AX78 (unless I give up on getting one that works from Scan)
250GB WD HDD

[TAKTAK]

RAID

redundant array of inexpensive/independant disks

There are number of different RAID levels:

Level 0 -- Striped Disk Array without Fault Tolerance: Provides data striping (spreading out blocks of each file across multiple disk drives) but no redundancy. This improves performance but does not deliver fault tolerance. If one drive fails then all data in the array is lost.
Level 1 -- Mirroring and Duplexing: Provides disk mirroring. Level 1 provides twice the read transaction rate of single disks and the same write transaction rate as single disks.
Level 2 -- Error-Correcting Coding: Not a typical implementation and rarely used, Level 2 stripes data at the bit level rather than the block level.
Level 3 -- Bit-Interleaved Parity: Provides byte-level striping with a dedicated parity disk. Level 3, which cannot service simultaneous multiple requests, also is rarely used.
Level 4 -- Dedicated Parity Drive: A commonly used implementation of RAID, Level 4 provides block-level striping (like Level 0) with a parity disk. If a data disk fails, the parity data is used to create a replacement disk. A disadvantage to Level 4 is that the parity disk can create write bottlenecks.
Level 5 -- Block Interleaved Distributed Parity: Provides data striping at the byte level and also stripe error correction information. This results in excellent performance and good fault tolerance. Level 5 is one of the most popular implementations of RAID.
Level 6 -- Independent Data Disks with Double Parity: Provides block-level striping with parity data distributed across all disks.
Level 0+1 -- A Mirror of Stripes: Not one of the original RAID levels, two RAID 0 stripes are created, and a RAID 1 mirror is created over them. Used for both replicating and sharing data among disks.
Level 10 -- A Stripe of Mirrors: Not one of the original RAID levels, multiple RAID 1 mirrors are created, and a RAID 0 stripe is created over these.
Level 7: A trademark of Storage Computer Corporation that adds caching to Levels 3 or 4.

the most commonly used being RAID 0 (speeds up access time as the data is spread between drives)
and RAID 5 where the data has a copy of the data on other drives (running backup)

EDIT: actually as staffsmike says RAID1 is a mirror, and RAID 5 has the ability to rebuild nazzed drives in the array and also spreads files over drives (my bad)

[staffsMike]

RAID 5 is actually used to stripe much like RAID 0 but each drive (must be 3 or more) stores the information to rebuild any hard drive that may fail in the array. It's the most expensive (due to the number of drives needed) but a very good way to gain performance and have a fairly safe backup.

RAID 1 is a direct copy or Mirror.

Yes you do need to start from scratch afaik.

[peterb]

The speed advantage that is alleged to come from RAID 0 is much overhyped IMHO. Unless you are using a dedicated controller, in specific situations, you are unlikely to notice much difference, and in some instances, writing to the disk can be slower. RAID 1 is useful for resiliance, particularly in server and 24x7 operations - but should not be considered as a substitute for backup. RAID 5 is normal for large dedicated server applications.

RAID is generally created when the disks are installed, although it is possible to have RAID partitions on two disks, if you are using software RAID - I'm ythinking here of the Linux RAID function. In that case you could create equal sized partitions on two or more disks and then create a RAID array from them. while having non RAID partitions on the same disks. That way you could transfer data across from the non RAID to the RAID partitions.

[mediaboy]

If you have to start from scratch I guess it's not something I'm going to do till I decide to get Vistax64 or till my next build

Thanks all!

[shaithis]

You can always install a raid controller into your pc, install the drivers for it and then image your system using something like ghost or acronis......

You can then create your raid and restore the image to your newly created array.

[mediaboy]

Just easier to wait 6-12 months till I start wanting more than 3 1/2 GB RAM

Besides.. I'm a little broke at the moment, so a new HDD is probably beyond me

[DataMatrix]

You don't need to start from scratch if you can copy the data from your previous setup to the RAID array, unless you don't mind reformatting of course.

[arthurleung]

Also note that overclocking does not mix well with RAID0/RAID5 (Not very sure about RAID1 though).

Dedicated hardware RAID card is not affected by overclocking but will cost you as much as a new non-overclocked machine.

In general RAID6 > RAID1 > RAID5 in terms of reliability (4 Disks), and RAID6 is coming to be a must for 8 Disks+ as you sure want to protect your 6TB+ array from mechanical failure. But will take away too much space with 6 Disks or less.

RAID3,4 is rarely used (Netcell / XFX Revo use RAID3).

[EtheAv8r]

Also note that overclocking does not mix well with RAID0/RAID5 (Not very sure about RAID1 though).

Please don't tell my PC that - it is running Intel Matrix RAID (0 and 1) and my E6700 is reliably overclocked from 2.66 to 3.56. See My System.

If my PC starts crashing I will know you told it! LOL