You can shorten all that to: Before you reboot and change the BIOS do this part as you listed
Make sure that the AHCI service is started during boot time. Goto HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msahci and set Start to 0 (at boot time)
Now reboot and go into the BIOS to switch the controller mode from whatever to AHCI.
Save your BIOS settings and reboot.
Make sure you press F8 and boot in to safe mode, install the correct driver
, reboot. Your Done.
Clean up if you wish.
I have done this many many times works perfectly. -WS