A graphics card is an integrated circuit card that enables a computer to display pictures on its monitor. Most graphics cards follow the VGA standard and support multiple resolution settings. Here’s how to install a new graphics card (or replace an existing card) on your computer.
Choose a graphics card that is compatible with your computer system.
Uninstall the existing graphics card drivers. To do that, right-click on "My Computer," select "Properties," click on "Hardware" and click on "Device Manager." In that section, you will find a head called "Display Adapter," under which you will find the listing for your existing graphics card. Double-click on that to find the "Properties" menu. Click on the "Driver" tab to find the "Uninstall" button.
Remove your existing graphics card. To do that, turn off your PC and disconnect all power supply. Open the CPU case and locate the AGP slot of your motherboard. This is found above the PCI slots. To prevent shock, secure yourself with antistatic wrist strap. Unscrew the graphics card from the back plate and remove it.
Load the new card. Insert it firmly and completely. Screw it to the back plate.
Install new drivers. If you use Windows XP, it will guide you through the installation process on its own; once the graphics card is installed and the computer turned on, the system will automatically detect the new device and prompt you to proceed with the installation.
Alternatively, open "Control Panel" and click on the "Add/Remove Hardware" option. The system will start looking for the new hardware (in this case, the new graphics card). If it does not detect a new graphics card, the system will prompt you to select from a list of existing cards or add a new device. Locate and select the correct graphics card from the list to begin installation. If you cannot find the graphics card, it is improperly connected or faulty. Check the physical installation and then with your graphics card vendor.