Make sure that your graphics drivers are up to date. You can download the latest Nvidia chipset drivers from http://www.nvidia.com/Download/index.aspx. You can download the latest AMD chipset drivers from http://support.amd.com/en-us/download. (Choose the correct site for your video card's chipset brand). If you have installed the latest updated drivers and are still having problems, try to adjust the graphics settings in games. Some computers will be unable to run games at max settings due to video card limitations. Typically when playing games with a new video card it may be best to let the software included with the card or the game itself set its graphics settings automatically and adjust settings from the automatic configuration.