The driver depends on the particular hardware, and can usually be found on your manufacturer's site if you search under Support for your model. You did not provide enough information for me to try the search for you.
Alternatively, a very clever member here posted directions on how to identify any hardware that needs a driver. See the second post here: http://www.tomshardware.com/forum/274306-45-video-controller-compatible-driver-windows-free-download , from Saga Lout.

Please satisfy my curiosity: how do you know that this is a driver issue as opposed to some other kind of problem?

Google Translate is your friend. If you are not comfortable in English, you can write a more detailed question in your best language and use Google Translate to change it to English. It may come out strange, but we will understand the point.