Which video card do you have? Go to your perspective AMD or Nvidia site and download the latest driver for your card. Go to "add or remove programs" if running windows and uninstall all ATI or Nvidia drivers, restart, then install the drivers you downloaded.
You don't upgrade your drivers for any particular game.....like any hardware part, you go to the part manufacturers web site and download the latest and greatest. Uninstall your current driver, reboot, install new driver.