How to change from IDE/AHCI to AHCI/RAID *without* reinstalling windows

[Temi_D]

Hi everyone. I installed windows in AHCI mode and I wanted to change my motherboard to RAID mode without reinstalling Windows. And I found a VERY EASY way to do it (from Microsoft) and it worked so I thought I'd share it with everyone.

It works if you want to change from IDE to AHCI, IDE to RAID, and AHCI to RAID

NOTE: It is recommended that you backup your whole system or the registry before attempting this (I did whole system backup). Nothing should go wrong but just in case

It is mostly what can be found here: http://support.microsoft.com/kb/922976 but with extra steps added to make it easier

1. Exit all Windows-based programs.

2. Click Start, type regedit in the Start Search box, and then press ENTER.

3. If you receive the User Account Control dialog box, click Continue.

4. Locate and then click one of the following registry subkeys (either one or the other; NOT BOTH):
"HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci"
"HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\IastorV"
I used the later

5. In the right pane, right-click Start in the Name column, and then click Modify.

6. In the Value data box, type 0, and then click OK.

7.On the File menu, click Exit to close Registry Editor.

8. Restart your computer, Enter the BIOS and change from IDE/AHCI to AHCI/RAID (depending on what you want). Save settings and exit

9. Reboot to windows and install the Intel Rapid Storage Technology (if you already have it installed, do it again).

10. Reboot and thats it! You should be able to access the new features in the Intel Rapid Storage Technology.

 

[bocsta]

setup raid 1 without data loss Win7 64

Thank you for these instructions

After my system build (for which I decided to leave the back up issue to later), I decided to switch to Raid.....

Reading the microsoft instructions I changed "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci" to 0 (it was the first one on the list)

which enabled me to change from IDE to AHCI but not from AHCI to RAID.

BIOS changes were possible of course but wouldnt boot successfully in RAID mode....only AHCI

After hours and hours of searching to see what alternatives there were and installing Intel® Rapid Storage Technology 9.6.0.1014, I finally changed

"HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci" back to its original value of 3

and changed "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\IastorV" to a value of 0


This enabled windows to boot with a RAID specified bios. I then reinstalled Intel® Rapid Storage Technology 9.6.0.1014 (as it hung after the 2nd set of registry changes), and used it to create my RAID 1 setup with Write-back cache enabled. Its currently migrating

 

[uv]

Is there a way to do the reverse of this process? Ie. disable RAID and switch back to normal AHCI without a reinstall?

 

[Cycrow]

the same process, you set the value to 0, then when you boot up next, windows will install the correct drivers.

theres also a simlar value you can set for just IDE mode

 

[bocsta]

For AHCI mode I'd try changing registry values of Msahci to 0 and IastorV to 3
For IDE mode I'd try changing registry values of Msahci to 3 and IastorV to 3
For Raid mode I'd try changing registry values of Msahci to 3 and IastorV to 0


Changing back from RAID 1 could work.... but I cant see you coming back from strip raids to IDE with simple registry changes