I tried this again and it worked! I changed Sata Operation to the "Raid Autodetect/ATA" and then did a clean install of Windows 8 (Google this procedure) from a dvd I created from the downloaded upgrade file (ISO). I had some problems finding the RAID Controller driver to display and delete the old partitions that Vista was saved on, but I eventually found it from browsing the Drivers CD that came with the laptop. Windows 8 then installed 100%, but at the very end of the process it gave me the error message "Your PC ran into a problem and needs to restart". When it restarts, press F12 to Repair and chose the Windows 8 DVD. From this point in I got the getting device ready message and then it installed Windows 8 successfully. Hope this helps!
Hi, I am having problems doing a clean install of Windows 8 (DVD) from Vista on my Dell Inspiron 1721. When I do a clean install, it can't find a device driver to load the partitions to be deleted. The driver should probably be related to the AMD Raid Controller, but it doesn't work when I try to locate what I think is the right file from a USB (hard to find the correct ifi file on the web). Am on the right track and I just need to find the correct driver file, or is there an easier way to do this (e.g. disable the Raid Controller)? I have been working on this for over a week with no success. Thanks for your help, Steve 
Windows 8 not installing on Dell Inspiron 1721