How to Enable AHCI Mode in BIOS/UEFI on a PC

To enable AHCI mode, open your PC's BIOS/UEFI setup, find the SATA or storage controller setting, change it to AHCI, then save and restart. That is straightforward on a new build or before installing Windows. If Windows is already installed while the controller is set to RAID, Intel RST, or IDE, do not switch the setting blindly: Windows can fail to boot with an INACCESSIBLE_BOOT_DEVICE error.

AHCI, or Advanced Host Controller Interface, is a controller mode for SATA storage. It enables SATA features such as Native Command Queuing (NCQ) and hot plugging on supported hardware. Intel's AHCI documentation explains that NCQ lets compatible drives accept and reorder multiple commands for more efficient random workloads.

Before you change the SATA mode

First, confirm that you actually need AHCI. AHCI applies to SATA drives and controllers. An NVMe SSD uses the NVMe protocol over PCIe rather than AHCI; the NVM Express specification overview describes NVMe as the interface used for PCIe SSDs. Some PC makers combine the wording in a setting such as “SATA/NVMe Operation,” but that does not turn an NVMe drive into an AHCI device.

Also take these precautions:

• Back up important files before changing storage-controller settings.
• Write down the current BIOS/UEFI storage mode so you can restore it if Windows does not boot.
• If BitLocker or Device Encryption protects the Windows drive, make sure you have the recovery key. Microsoft recommends suspending BitLocker around some firmware and UEFI changes; see the BitLocker suspension guidance.
• Do not switch away from RAID if you have an active RAID array. Changing the controller mode can make the array or Windows installation inaccessible.

Enable AHCI in BIOS/UEFI before installing Windows

1. Shut down the PC.
2. Power it on and repeatedly press the firmware setup key. Delete and F2 are common, but the correct key depends on the manufacturer. ASUS documents F2 for many systems and Delete on some desktops in its BIOS entry guide.
3. Open a menu named Advanced, Storage, Integrated Peripherals, SATA Configuration, or similar.
4. Find SATA Mode, SATA Operation, or Storage Controller Mode.
5. Select AHCI.
6. Choose Save & Exit, often with F10, and allow the PC to restart.

The menu layout is motherboard-specific. For example, MSI's official storage-detection guide shows a SATA Mode setting that can be changed to AHCI. BIOS names and locations still vary by model.

Switch an existing Windows installation to AHCI safely

If Windows was installed while the controller used RAID, RST, or another mode, prepare Windows to start once in Safe Mode before changing the firmware setting. Dell documents this approach for systems that otherwise blue-screen after a SATA-mode change, and Microsoft documents BCDEdit as the Windows tool for changing boot configuration.

1. In Windows, open Command Prompt as administrator.
2. Run bcdedit /set {current} safeboot minimal.
3. Restart the PC and enter BIOS/UEFI.
4. Change the storage controller from RAID/RST/IDE to AHCI, then save and exit.
5. Windows should start in Safe Mode. Open Command Prompt as administrator again.
6. Run bcdedit /deletevalue {current} safeboot.
7. Restart normally.

You can verify the command syntax in Microsoft's BCDEdit documentation and compare the workflow with Dell's SATA-mode recovery procedure.

What if Windows will not boot after enabling AHCI?

Return to BIOS/UEFI and restore the previous storage mode. Dell notes that changing between AHCI and RAID can trigger INACCESSIBLE_BOOT_DEVICE when Windows is not prepared for the new controller mode. Once Windows boots again, confirm that the required storage drivers are installed, then use the Safe Mode procedure above if the machine and storage configuration support AHCI.

If there is no AHCI option at all, do not try to create one with a Windows Registry edit. The available controller modes are determined by the motherboard, firmware, chipset, and OEM configuration. Check the PC or motherboard manual for the exact storage settings supported by your model.