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
    2012-12-05T18:47:41+00:00

    Thank you so much for the Answer ......!!!! It worked for me.

    I my office Macfee encryption software was not working with Raidon mode. so i should move to AHCI mode to install the same. It was giving blue screen error for me when i move to AHCI mode.

    So I have chaned the reg values now it started booting in AHCI mode.

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  2. Anonymous
    2012-10-19T01:31:53+00:00

    Thanks so much. I imaged a raid array using Acrois, restored the image to a single drive and changed to ahci mode after using this method. worked perfect.

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  3. Anonymous
    2012-07-11T21:03:12+00:00

    This resolved my problem where a fresh install on a Dell laptop was set to RAID by default, even though it only has one drive. This kept creating a "hanging" issue on reboots, sometimes requiring manual power off/on. Changed to AHCI mode and got startup issues that were not resolved by Startup Repair. The reg changes resolved the problem. Thanks O. Bilal.

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  4. Anonymous
    2012-02-15T22:02:37+00:00

    Try enabling for the below drivers as well, and let's see if it solves for your hardware.

    HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\nvstor

    HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\nvraid

    HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\amdsata 

    HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\iastor //this one might not be there for every machine. If it is missing for yours download theIntel(R) Storage Drivers and check again.

    Thanks

    The 'amdsata' driver resolved this for me - thank you for explaining why.

    This was an Asus M5A99X Evo motherboard with an AMD SB950 Southbridge chipset. I had already installed chipset and AHCI drivers.

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