Changing from RAID to AHCI

Anonymous
2010-10-28T12:24:52+00:00

Hi,

on my Dell E6510 I have my disk drive set to RAID mode. I have issues using the eSata port so I want to switch to AHCI. I followed the instructions here:http://support.microsoft.com/kb/922976. However when I boot my system after setting the disk mode to AHCI in the BIOS I see the Windows logo (using Win7 x64) and some seconds later I get a bluescreen with a message I can't read because the system is rebooting. Changing the BIOS back to RAID brings up the system again...

Anything I can do to make AHCI working?

Thanks,

Thomas Pagel

Windows for home | Previous Windows versions | Devices and drivers

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Anonymous
2010-11-03T18:05:23+00:00

Hi Thomas,

Thank you for your post.

I believe I have the solution to your problem and I verified it against a Dell machine that has similar controller with your machine. Changing from AHCI to RAID,http://support.microsoft.com/kb/922976 fix will work.  

Changing from RAID to AHCI, you need one more step. Msahci driver requires Atapi.sys miniport to be loaded during boot as well. So you need to change theStart value to 0 for both of the following entries in your registry. You can use regedit.exe utility. 

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\msahci

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\atapi

Or you can also simply run the below command lines in an elevated window.

REG ADD HKLM\System\CurrentControlSet\Services\msahci /v Start /d 0 /f /t REG_DWORDREG ADD HKLM\System\CurrentControlSet\Services\atapi /v Start /d 0 /f /t REG_DWORD

Regards

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  1. Anonymous
    2010-10-28T16:14:06+00:00

    Hi,

    My guess is that when you are changing to AHCI you are also "disassembling" the RAID.

    RAID is an array of multiple disks connected to your SATA ports.

    SATA ports have two flavors in BIOS: native IDE and AHCI, being the latest the most advanced one.

    You should switch to AHCI in BIOS, but at the same time maintain the RAID structure.

    Please read your motherboard manual very carefully on how to set up a RAID array with SATA AHCI interface.

    You have now a RAID array configured with SATA "native" interface.

    Carlos

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  2. Anonymous
    2010-10-28T16:16:14+00:00

    Well, there is nothing to "disasseble" because I have two drives connected to the controller which are completely independant... So I don't have any RAID volumes defined... Thanks,

    Thomas Pagel

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  3. Anonymous
    2010-10-28T16:46:19+00:00

    Also reset the CMOS  and maybe you need to update the BIOS.

    mohanad

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  4. Anonymous
    2010-10-28T17:17:51+00:00

    well, it's a notebook so resetting the CMOS doesn't make much sense and since I use bitlocker this would be a risk... The BIOS is up to date...

    Thomas Pagel

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