If you installed Windows 10 with the disk controller set into the IDE mode in the BIOS, you cannot switch it to AHCI directly and hope that Windows will work correctly. Once you change it in the BIOS, Windows 10 will become unbootable. To avoid this, you need to follow the instructions in this article.
Advanced Host Controller Interface (AHCI) is a technical standard defined by Intel that specifies the operation of Serial ATA (SATA) disk controllers. When it is supported by your operating system and PC hardware, you will get the benefits of features such as native command queuing and hot swapping. For an older OS like Windows XP which does not support AHCI mode out of the box, without OEM-supplied drivers, it is possible to turn on the legacy (IDE) mode in the BIOS to get it to install properly. If your installed your Windows 7 or Windows 8 accidentally in the legacy IDE mode, and want to switch to the AHCI mode, Windows will not boot after you switch from IDE to AHCI in the BIOS. Here is how to fix it.