Double Screenage

I just ordered a Mini VGA=>VGA adapter so I can hook my iMac up to my old 19inch flatscreen monitor. Need to use a program called Screen Spanning Doctor to enable it, as it’s not available by default, but the computer is more than capable of doing it. Apparently it’s so they can differentiate between lower and higher end products. On the webpage of this “hack” it says it may cock the computer up…but I have not found one case of that happening. So fingers crossed it works for me.