geht aber einfach bei vista :
Exit all Windows-based programs.
Click on Vista Start Menu, type regedit in the Start Search box, and then press ENTER.
If you receive the User Account Control dialog box, click Continue.
Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci
In the right pane, right-click Start in the Name column, and then click Modify.
In the Value data box, type 0, and then click OK.
On the File menu, click Exit to close Registry Editor.
Restart computer, and enable ACHI mode in BIOS again. This time the computer should be able to boot up properly without error or BSoD.