How to open AHCI mode of win7 system

            Many friends should have found that when installing win7 64-bit Ultimate download, the ahci function in the hard disk can not start the system under the BIOS. Only change the IDE mode back, so that the system can start normally. Even if you install win7 system in IDE mode, you need to reinstall the system to change to ahci mode. So, is there any way to let us not reinstall the system, you can directly open the ahci mode of the hard disk? Below, Xiaobian Let's talk about the specific operation method for everyone!
1. Click the start menu in the lower left corner of Win7 64-bit Ultimate, then type regedit and click Enter.
2. After opening the computer's registry editor window, we will expand HKEY_LOCAL_MACHINE\\SYSTEM\\ CurrentControlSet\\services\\msahci in the menu on the left, so that we can find the strat option in the right window.
3. Double-click the strat option found above, an edit window will pop up. Let's change the value data directly to 0 (the default value of the computer should be 3), then change the cardinality to hexadecimal.
4. Close the Registry Editor window, and then restart the computer, the above settings will take effect.
5. When we restart the computer, we can try to enter the BIOS interface, and then change the hard disk to ahci mode. Now, do you find that you can enter the system normally?