Questions about RAID

Temi_D · 29 Sep 2009 at 22:57

1. I heard that if you clone a non raid windows installation and move it to a raid configuration, it doesnt work. What about if its the other way around? will it work then? as in raid to non raid

2. What are the approximate gains (%) in using 2 HDDs in raid 0 vs non raid? In mainly concerned about write speed

Any help would be greatly be appreciated, thanks in advance

NightmareXX · 30 Sep 2009 at 00:26

Either way will work as drives that are in RAID are transparent to the OS.

Well, it's usually about 1.5x better at least. Largely depends on what you're writing, stripe sizes, cache, blah blah blah.

rpstewart · 30 Sep 2009 at 08:42

Temi_D said:
1. I heard that if you clone a non raid windows installation and move it to a raid configuration, it doesnt work. What about if its the other way around? will it work then? as in raid to non raid

Going non-RAID to RAID will only work if you have the RAID version of the SATA controller drivers installed before you start. It's do-able but a bit of a pain.

RAID to non-RAID will work without problems.

Temi_D said:
2. What are the approximate gains (%) in using 2 HDDs in raid 0 vs non raid? In mainly concerned about write speed

Any help would be greatly be appreciated, thanks in advance

As stated sustained read/write speeds will be somewhere around 1.5-1.8x that of a single drive. However the random access time will actually go up a bit compared to a single drive.

SMAndy · 30 Sep 2009 at 12:02

rpstewart said:
Going non-RAID to RAID will only work if you have the RAID version of the SATA controller drivers installed before you start. It's do-able but a bit of a pain.

Sorry, what do you mean by this? Can you just, as an example... run on a single drive for a while, install the RAID/AHCI drivers while in windows/other OS, and copy a drive image onto a RAID partition? Or do you have to do the registry fix to alter the driver being used? I know its a similar change you have to do to switch to a single drive with AHCI enabled...

rpstewart · 30 Sep 2009 at 16:51

It's basically the same process as for going from IDE mode to AHCI.

ChileanLlama · 30 Sep 2009 at 20:02

SMAndy said:
Sorry, what do you mean by this? Can you just, as an example... run on a single drive for a while, install the RAID/AHCI drivers while in windows/other OS, and copy a drive image onto a RAID partition? Or do you have to do the registry fix to alter the driver being used? I know its a similar change you have to do to switch to a single drive with AHCI enabled...

You basically need to frig the registry and load up the RAID drivers _before_ you create the image of your single drive, then create the RAID0 (wiping the disks) and restore the image. Because the image contains the RAID drivers it should work fine.