Switching the BIOS SATA's Mode from IDE to AHCI

I've seen much discussion on the web about how to switch the BIOS Serial ATA (SATA) boot drive from IDE mode to Advanced Host Controller Interface (AHCI) mode in existing Windows installations. AHCI exposes SATA's advanced features, including reduced CPU overhead and hot-plug and power-management capabilities. If you're running Windows 7 or Windows Vista, there's a registry tweak to switch to AHCI mode, which I haven't tried yet. If you're running Windows XP, you're not out of luck. If your motherboard has an IDE port, switching is relatively simple. Here's how to do it:

1.     Download the "F6" driver files for your SATA controller chipset. (They're referred to as the F6 driver files because they were the files that you'd put on a floppy disk and use during a Windows OS installation when prompted to Press F6 if you need to install a third party SCSCI or RAID driver.) You can download the driver files from your motherboard manufacturer's website or use the files found in the motherboard's installation CD-ROM. For example, on an ASUS P5E3 motherboard CD-ROM, the files for the Intel ICH9R SATA controller are found in D:DriversChipsetMakediskDOS32bit (or 64bit). Alternatively, for well-known manufacturers, you might be able to find the F6 driver files for your chipset by searching the web (e.g., search for "F6 ICH9R"). Put the driver files into a new directory (e.g., C:ICH9R) on the existing SATA boot drive, which I'll refer to as SATA-01.

2.     Using an imaging program (e.g., Acronis True Image, Symantec's Norton Ghost), make a full disk backup image of SATA-01 and save the image to a different spindle (e.g., F:SATA-01SATA-01.tib, F:SATA-01SATA-01.gho) or removable drive. Make certain to use the imaging program's verification function to verify 100 percent integrity of the SATA-01 backup image.

3.     Make another full disk backup image of the SATA-01 boot drive, saving it to a different spindle (e.g., G: SATA-01SATA-01.tib, G: SATA-01SATA-01.gho) or removable drive. Once again, verify 100 percent integrity of the backup image. This second backup image isn't needed for the switch, but it provides an extra layer of protection in case of operator error. If an error occurs, you shouldn't use the second backup image for the restore operation. Instead, make a copy of it and use the copy for the restore operation. I learned this lesson the hard way. I once had a restore operation hang because of a bad destination disk and the hang corrupted the backup image.

4.     Shut down and physically disconnect the data and power connections to the SATA-01 boot drive. Mark the boot drive with tape or a label that says SATA-01. You can either remove the boot drive or leave it in the machine. I recommend that you remove the boot drive and set it aside for safety reasons.

5.     Connect an IDE drive of suitable byte size to an available IDE cable. If your motherboard has only one IDE port, set the IDE drive to Master with Slave Present and the CD-ROM/DVD drive to Slave (or set both to Cable Select). If your motherboard has two IDE ports (usually one cable for two hard drives and the other cable for two CD-ROM/DVD drives), put the IDE drive on one cable by itself and set its jumpers to Single (or Master with Slave Present if you have two IDE drives). Put the CD-ROM/DVD drive(s) on the other cable and configure the jumpers appropriately (i.e., one Master and the other Slave, or just use Cable Select for both). Note that having a second IDE drive present when switching to AHCI mode is possible, but it introduces additional opportunities for operator error.

6.     Connect a different preformatted SATA drive to the same data and power connectors that were previously connected to SATA-01. I'll refer to this drive as SATA-02. You aren't required to use a second SATA drive when you make the actual switch—you can use SATA-01. However, I recommend that you use a different SATA drive (i.e., SATA-02) for safety's sake. If you decide to use the original SATA-01 boot drive, make sure that you're 100% comfortable with your backup image and imaging program's restoration process.

7.     Boot up using your imaging program's boot CD-ROM. You might need to change the boot order in the BIOS so that it boots from the CD-ROM drive first. Note that some BIOSs let you press F8 or F12 (or some other key combination) after power-on to select the boot device.

8.     Restore the F: SATA-01 backup image (including all partitions and the Master Boot Record—MBR) to the IDE drive. I realize that it's possible to simply clone one drive to another, but for safety's sake, I prefer to get the original SATA-01 boot drive out of harm's way, as recommended in step 4.

9.     Reboot and change the BIOS SATA from IDE mode to AHCI mode. Also change the BIOS boot order so that it boots the OS from the IDE drive.

10.  Boot into the OS (which is now on the IDE drive). Windows should see the attached empty preformatted SATA-02 drive and either install the Windows default AHCI drivers automatically (in which case you won't need to use the SATA controller manufacturer's F6 driver) or prompt you for the location where you saved the manufacturer's F6 driver (e.g., C:ICH9R). SATA-02 should now show up in Windows Explorer as a drive (e.g., E:).

11.  Shut down Windows and use your imaging program's boot CD-ROM to clone the IDE drive to the SATA-02 drive.

12.  Shut down, disconnect, and remove the IDE drive.

13.  Set the BIOS to boot the OS from the SATA-02 drive, which will now become the boot drive.

14.  Boot into the OS. The AHCI driver will be automatically used for SATA-02.

At this point you can continue to use the SATA-02 boot drive and the switch is complete. However, if you prefer to use your original SATA-01 boot drive for production (like I did), you can:

1.     Make a final backup image of the SATA-02 boot drive to an available spindle or removable drive.

2.     Shut down and replace the SATA-02 drive with the SATA-01 drive.

3.     Use your imaging program's boot CD-ROM to restore the final SATA-02 backup image to the SATA-01 drive.

You might be tempted to use your imaging program's boot CD-ROM to clone SATA-02 to SATA-01 instead of restoring SATA-01 from that final backup. However, if something goes wrong (i.e., think operator error), you could potentially lose both disks.

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