Hi pawello,
Let me help you with this.
As you mentioned, the WiDi is certified to work on windows environment but It is necessary to meet the necessary requirements. It is also important to say that OEMs most of the times set limitations on their units for special features.
Here you have the WiDi Requirements information:
My best recommendation is for you to contact the Computer Manufacture and confirm with them if the computer supports the WiDi feature.
Kevin M