32

My Dell XPS 9560 uses RAID as a SATA controller mode.

After I change it to AHCI, the Windows 10 will not boot.

What should I do if I don't want to reinstall Windows 10?


RAID = Redundant Array of Inexpensive Disks, wikipedia link.
AHCI = Advanced Host Controller Interface, wikipedia link.

3 Answers 3

8

You need to install the correct driver for your AHCI storage controller before changing the mode in the BIOS.

If you don't do so, after switching the mode Windows cannot load the storage controller driver needed to access the boot volume. Because this driver is loaded before the Plug and Play Manager, Windows can't automatically detect or otherwise search for the correct driver.

Pre-installing the driver should solve this.

That said, you don't mention the reason you want to do this, but if it's for reason of performance, in my experience there's no difference between the two modes on Dell XPS machines.

1
  • This information is wrong and misleading, and should not be the top answer. It is not necessary to reinstall storage drivers. Windows will do this itself if started in Safe Mode. Jul 22, 2022 at 12:35
77

There is actually another way around this. Before you begin, make sure you remember your PC password (not PIN), or else you would be stuck in safe mode forever (with this way of entering safe mode). Also, I advise you to disable BitLocker before entering safe mode, or else you would probably need to provide a very long code to unlock your computer (not tested).

Booting into Safe Mode will work even though the storage mode has been changed... Windows will notice the change and load the correct driver on the next normal boot. Basically that means, you can do this:

  1. Run cmd as administrator (not PowerShell, you would have to escape {...})

  2. Copy-paste this command, which will start Windows in Safe Mode the next time you reboot:

    bcdedit /set {current} safeboot minimal
    
  3. Restart the computer and enter UEFI/BIOS setup.

  4. Change the SATA operation mode from RAID to AHCI.

  5. Save changes and exit Setup and Windows will automatically boot to Safe Mode.

  6. Launch cmd again, as in step #1.

  7. Copy-paste this command, which will start Windows in Normal Mode the next time you reboot:

    bcdedit /deletevalue {current} safeboot
    
  8. Reboot and Windows will automatically start with AHCI drivers enabled.

Note: Switching to AHCI is essential if you want to install any Linux as RAID mode is to my knowledge not supported, so you would not see your drive(s) in the installation menu.

16
  • 3
    Thanks, this was the solution in my case. I installed Fedora along side my Windows installation on an XPS laptop, but to do so, I had to switch to AHCI so Fedora could see my storage drives. After doing so, Windows wouldn't boot. This allowed me to use Windows in AHCI. Thanks again.
    – root
    Mar 2, 2019 at 15:29
  • 6
    This worked for me on a Dell Precision laptop. However, instead of using command prompt I just set Windows 10 to boot once to safe mode by going to Change advanced startup options -> Adanced startup ->Troubleshoot -> Advanced options ->Startup Settings -> Restart. Then change SATA to AHCI before booting to safe mode and the SATA driver updates automatically once safe mode boot completes.
    – Teddy Ort
    May 31, 2020 at 0:59
  • 3
    @TeddyOrt You are correct, that is also an option, but a bit cumbersome for me, so I'll leave the original command in place. Thanks for the info still, cheers! May 31, 2020 at 7:00
  • 2
    This just worked for me on a Latitude 5420 with Win10 21H1, although there are various posts from Dell techies on Dell's fora saying it's impossible and you must reinstall. Afterwards I could confirm that Ubuntu Unity 21.10 was able to see and read/write my NVMe SSD. Nov 8, 2021 at 11:06
  • 2
    This worked for me, except I just used the Windows 10 settings way of booting into safe mode on next reboot. Before going into safe mode I disabled RST. Dec 19, 2021 at 21:59
11

Warning: If you have bitlocker enabled, save your recovery key elsewhere (or write it on paper) before attempting to change to AHCI. You will need it for safe mode boot.

If windows fails to boot three times, it lets you boot into safe mode. When it shows the Choose an option screen, get to safe mode: Troubleshoot -> Advanced Options -> Advanced Startup Options -> Startup Settings -> Restart. Once restarted, choose 4 (safe mode).

Once the computer has booted into safe mode (and automatically installed the AHCI driver), you are free to restart normally.

2
  • 1
    This is enough for me. No need to type commands.
    – criticabug
    Dec 21, 2021 at 3:55
  • This is the much better solution. No risk of getting stuck in safe mode, no admin password required, no commands needed. Jan 30, 2022 at 14:54

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .