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 specify the make or model, which are needed to identify drivers.
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-contr... , 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?