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If you haven't updated your graphics card drivers in a while, you'll want to get the latest version. Updated drives can make a big difference in performance, especially for older cards. You can figure which drivers you need by opening the Device Manager. Open the Start menu or screen and type "device manager" to find and open it. This will show all of the graphics adapters that you have installed. You will likely only have one or two items listed here. The "Display adapters" section will show the current model of your graphics card. If you have an Intel and an AMD or NVIDIA entry, you can ignore the Intel entry. The model of your graphics card will be listed after the manufacturer (i.e. NVIDIA GeForce GTX 670) When you have two adapters listed here, one if for your motherboard and the other is for your graphics card. The motherboard graphics will almost always be Intel, and is not used if your monitor is connected to a graphics card from NVIDIA or AMD. You'll be able to download drivers directly from the manufacturer's website. Below are the driver download sites for the major manufacturers:  NVIDIA - http://www.nvidia.com/Download/index.aspx  AMD - http://support.amd.com/en-us/download  Intel - https://downloadcenter.intel.com/ Use the search function or the automatic driver detection feature on the driver website to find the correct download. All of the major manufacturers can automatically detect your adapter and download the correct drivers for you. Most driver installers are about 300 MB in size, and may take a little while to download. After you download the driver installer, run it from your Downloads folder to begin installation. The installation may take a while, and your screen may flicker or go black during it. Decline the installation of any driver management software like GeForce Experience, as these typically just make your games run slower when they're open.
Open the Device Manager. Expand the "Display adapters" section. Find your graphics adapter model. Visit the manufacturer's website. Find the driver download for your graphics adapter. Run the installer.