what operating system are you using?
(e.g. windows xp/linux/mac/vista?)
in windows vista (and perhaps xP) to see what video card your using, right click "my computer" and choose "manage" than click "device manager" from the list to your left. click the "plus (+)" next to "display adapters"
and you 'should' see the name of the video card. go online and type the name.. follow by, driver.
and you should find the driver. =]