No need to reinstall the system Windows 7 directly open AHCI

I believe that many of my friends will encounter the AHCI function of the SATA hard disk in the BIOS after installing Windows. I recently encountered this problem when I started installing AHCI after installing Windows 7. Only after changing back to IDE mode, the system will return to normal. After testing, I found that if I installed the Windows system in IDE mode, if I want to change the hard disk to AHCI mode in the BIOS, I need to reinstall the system. So is there a way to open the AHCI mode of the hard disk without reinstalling the system? After some research and consultation, I finally found the following solutions.

Open AHCI mode after modifying the registry

1. Click the "Start" button, type "regedit" in the search box, press the Enter key to open the "Registry Editor" window. Although Windows 7 does not display the "Run" command by default in the "Start" menu, it can actually be replaced with a search box (or directly by pressing the Windows key + R key).

2. In the title bar on the left side of the Registry Editor window, navigate to the HKEY_LOCAL_MACHINE\\SYSTEM\\ CurrentControlSet\\services\\msahci branch, then in the right window, double-click Start.

3. In the "Edit DWORD Value" dialog box that opens, change the value in the "Value Data" box from 3 to the number 0 and click the "OK" button.

4. Close the Registry Editor window and restart your computer.

5. When the computer is restarted, enter the BIOS setup interface and change the hard disk to AHCI mode. For example, for the author's computer, press the F1 key to enter the BIOS when starting the computer, select Devices→ATA Drives Setup→Configure SATA as→AHCI, and finally press F10 to save and exit the BIOS.

After modifying the registry and enabling the hard disk AHCI mode as described above, you can start it normally without reinstalling the system. Although the startup speed of the computer will not change, when you copy a large number of files, you can see that there is a certain acceleration effect.

Summary:

Of course, there are a few points to pay attention to when doing specific operations.

Different motherboards enter the BIOS shortcut keys and the location of the AHCI item in the BIOS is different. You can read the manual attached to the motherboard to confirm.

Normally, the BIOS is enabled by default in the IDE mode of the hard disk, and AHCI is the abbreviation of Advanced Host Controller Interface, which means the advanced host controller interface, which is a technology led by Intel. It can improve the speed of SATA hard disk to a certain extent, it is recommended to open it.

In Windows Vista SP1 and later systems, the driver is automatically installed after the BIOS changes the hard disk to AHCI mode. But if you are using the operating system before Vista SP1, you need to manually load the AHCI driver through the Windows installation CD when you start the computer. If there is no installation CD for Windows system, please change back to IDE mode, download and install AHCI driver after booting the computer, then enter BIOS to change hard disk to AHCI mode.