I currently use TI 8 and have downloaded and installed the the trial for V9. Can anyone advise on what the differences between the upgrade and the full version are. Since I have v8 already installed I imagine installing the upgrade would be straightforward. However, I plan on replacing my PC soon, and would be installing V9 onto a clean OS. What would be the procedure if it were an upgrade - i.e. do I need to install V8 first or perhaps enter the key for V8 as well as the key for V9? Thanks.