Increasing the fan speed of a graphics card will make it run cooler and help to preserve its lifespan. Increasing the speed is also a good idea if you have overclocked the graphics card. Most modern graphics cards can easily have their fan speed manually altered simply by using the updated drivers from either ATI or nVidia, depending on your model of graphics card.
Go to nVidia.com and download the latest drivers for your graphics card and operating system if you do not have them already. Install the drivers and restart the computer when prompted.
Download and install nVidia System Tools. These will add various advanced settings to your nVidia Control Panel, including a fan speed control.
Right click on your desktop and click "NVIDIA Control Panel". Select the "Performance" menu on the left-hand side of the menu. Select "Device Settings". Click the "GPU" icon at the top-right of the page and locate the "Cooling" section at the bottom. Change the fan speed to your desired value.
Close the Control Panel. When the message "Would you like to load the saved settings at Windows start up" appears, click "Yes".
Open your web browser and navigate to ati.com. Download and install the latest drivers for your graphics card and operating system. Install the drivers and restart the computer when prompted.
Right click on your desktop and open up the ATI Catalyst Control Center. Access the Advanced Configuration Menu by clicking the "Advanced" option at the bottom-left corner.
Select the "ATI Overdrive" page from the menu on the left-hand side. Select the box "Enable Manual Fan Control" and move the slider to your preferred setting. Click "OK" to confirm.