I had Original Vista in Swedish language  installed in my Lenovo Thinkpad T61.  When I tried to install Windows XP it showed some error saying it didnt actually find the hardisk. I have digged the net and found that other people also suffered the same problem. But unfortunelty I really had to search hard to find the solution. This is very obvious as there are not many people who have thier hands on this monster. 

Here is the trick in simply one line. Go to the bios, change the SATA from AHCI to Compatible, and then Install anything you want starting from Windows XP to Windows 95. Wait a second dont leave just because you have the XP installed, there is a bit more to it, you have to install some of the drivers manually.  

  1. You need to install this UAA High Def Audio Driver before you move on to installing things in step 3.
  2. HotKey Driver – If you have bluetooth installed, you’ll need this to use fn + F5 to enable it for the bluetooth installation.
  3. Install the rest of the drivers like Intel Ethernet driver, Bluetooth software, Audio software, ACPI power management, wireless card, and modem driver. Get them here.

Great now you have everything running.. Now its time to Enjoy !