I already did the a registry change to solve any issue in Win 7. I will still look at your link as the registry key I changed in 7 does not exist in 8.1.
Turns out that the registry change I made is the same as in the link. However it does give another key that may apply according to the system...
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\IastorV
It would seem that the fix for Windows 8/8.1 is to boot normally in Native IDE or ATA SATA mode then set Windows to boot to Safe Mode via an elevated Command prompt with the following command.
Code:
bcdedit /set {current} safeboot minimal
Boot to the BIOS and change the SATA setting to AHCI and boot to Safe Mode.
Again via an elevated command prompt enter
Code:
bcdedit /deletevalue {current} safeboot
The system should now boot correctly to Windows 8/8.1.
I have not yet tried this but will let you know.
In either case all that is being done is to enable a driver for the different SATA mode. In Windows 7 it is done with a registry key and in 8.1 it is handled automatically by Safe Mode.
<edit> The command prompt did not work as expected. Win 8.1 did not load to Safe Mode. I MAY try making the boot change via EasyBCD to see what happens but I'm done for now. Making this switch for 8.1 is just playing anyway. Since the 8.1 drive is not normally even connected to the machine I can just as easily change the SATA mode in the BIOS when I do connect it. Also, since it is a raw install that isn't even updated, I could just install it with AHCI enabled. I'll play first though.
One thing that AHCI allows that I didn't know is the hot swapping of SATA drives. Not that I'll use it but nice to know.