Well I have tried a and finally given up on making my 716sa work with my computer. The drive diagnostic says that it works fine and when I leave my computer alone it works fine but it there is any other traffic on the SATA bus then I have read and write errors. The drive is fine but there is something wrong with the computer! Well sucks to be me, all that wasted time and now it is time to move on to a BenQ drive.
If you are interested in a perfectly working plextor px-716sa you can find it here: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=8786241583 and help me pay for a new drive!
I hope the SATA thing works out better for everyone else!