Every modern graphics card has a built-in sensor for monitoring the card's temperature and adjusting its cooling fan accordingly. In some cases, however, you may want to manually set the card's fan speed. For example, some fans are particularly noisy, and lowering their speed can reduce or even eliminate this noise without adversely affecting the card's temperature. On the other hand, some cards are prone to overheating, and increasing their fan speed can keep them cooler and prolong their life. Either change is simple to make, although the process varies slightly depending on whether you have an ATI or an NVIDIA card.
Open ATI Catalyst and select "ATI Overdrive" in the drop-down menu at the top left of the program window. ATI Catalyst is included with all ATI graphics cards and should already have been installed as part of the driver installation process. If you haven't installed it yet, the most recent version is available at the AMD website.
Click the "Enable ATI Overdrive" box to enable manual graphics card settings, then click the "Enable Manual Fan Control" box to allow changes to fan speed. Note that while you can check the "Enable Manual Fan Control" box without also checking the "Enable ATI Overdrive" box, any changes to fan speed will be ignored until both boxes are checked.
Set the slider under the "Enable Manual Fan Control" box to a value between 20 per cent and 100 per cent. Values under 20 per cent aren't allowed because they risk damaging the card.
Click the "Apply" button to change the fan speed, then click the "OK" button to finalise the settings and exit the program.
Open NVIDIA System Tools and select "Device settings" in the "Select a Task" menu at the left of the program window. NVIDIA System Tools is included with all NVIDIA graphics cards, but its installation is separate from driver installation. If you haven't installed it yet, the most recent version is available at the NVIDIA website.
Click the "GPU" icon in the "Create Profiles" tab.
Set the "Cooling" slider at the bottom of the window to a value between 0 per cent and 100 per cent. The fan will now run at that speed.
Exit NVIDIA System Tools. Before it closes, it will ask you, "Would you like to load the saved settings at Windows start up?" Click the "Yes" button if you want to load the new fan speed each time you start Windows. Otherwise click the "No" button, in which case you will have to open NVIDIA System Tools again to change the fan speed in the future.
Reducing fan speed to the point that it can no longer cool the video card may result in permanent damage to the card.