I've been looking for days the answer on the Internet but still unable to find it. I asked to Startech Support and here is the answer :
"Thank you for contacting StarTech.com.
We apologize for any inconvenience this may have caused. Unfortunately we are unable to provide a solution or support for this adapter when used on a Linux environment as the device was not intended to be used under Linux. Although you are using WINE for the adapter, there is no certainty the software will work.
If you have any other concerns, please do not hesitate to contact us again."
So here I am to ask if someone get the solution. I know it's something really basic like some line of command, things like that but i'm still a newbie on Ubuntu.
Note : I already installed the driver from the CD-Rom with WINE and also tried w/ the driver from the website. Still can't manage to have a dual screen display. Btw it works nicely on Windows but I'd like to use Ubuntu for work.
Awaiting for answers.