A computer contains several fans to keep it cool. When a computer is first turned on, the fans normally spin at high speed and create some noise. After 5 to 20 seconds, however, the fan noise stops.Fans that continue to spin at high speed or make strange noises might indicate a problem. If the fan is still noisy after 20 seconds or if a fan suddenly starts making unusual noises, use the following steps to troubleshoot for problems.
Step 1: Adjusting the power settings in Windows 7
Some power settings cause fans to spin too fast for a typical household environment. If you are using the computer in a quiet environment where temperatures remain steady and mild (up to 30 degrees Celsius or 86 degrees Fahrenheit), adjust the power settings to a lower energy usage. Use the following steps to adjust the power settings:
Turn on the computer and wait for Windows to open.
Click Start and type power plan in the Search box. In the search results, click Choose a power plan.
Figure 1: Choosing a power plan
3. Click Power Saver and close the window.
Figure : Selecting a power plan
4. Restart the computer.
If the fan is quiet, the problem is solved.
If the fan is still noisy, continue to the next step to determine which fan is noisy.
Step 2: Locating a noisy fan
Turn off the power and remove the computer side panel to locate the noisy fan.
Turn off the computer.
Remove any objects near the computer. In addition, make sure there are no children or pets near the area.
To open the computer case, loosen or remove the screws at the back of the side panel. Then slide the panel to the back and away from the computer.
WARNING: Do not put any part of your body inside the computer. Touching components inside the computer, even when the computer is off, can damage sensitive electronic circuits and expose you to risk of injury from electrical shock.
4. With the side panel removed, turn on the computer and listen for fan noise inside the computer
5. Find the noisy fan and remember its location.
NOTE: If the fan noise goes away when the side cover is removed, the problem might be caused by excessive heat inside the computer case.
6. Turn off the computer.
7. Replace the side panel.
Step 3: Determine which type of fan is making the noise
You can identify the fan type by its location within the computer. Use the following information to find which type of fan is making the noise.
The noisy fan is inside a metal box inside the computer case, usually at the top and back. This is a power supply fan.
The noisy fan is attached to a graphics adapter, a circuit board fitted into a plastic slot on the motherboard. This is a graphics adapter fan.
The noisy fan is the largest fan on the main circuit board inside the computer. This is a processor fan.
The noisy fan is inside the case, usually at the back. This is a case fan.
After finding the noisy fan, continue to the next step.
Figure : Examples of fan locations on a desktop computer (your computer should look similar)
Power supply (might contain a fan)
Graphics card fan
Processor fan
Case fan
Power supply fan vent (back view)
Case fan vent (back view)
Figure : Examples of fan locations on a Slimline computer (your computer should look similar)
Power supply (might contain a fan)
Processor fan
Graphics adapter fan
Power supply fan vent (back view)
Case fan vent (back view)
Courtesy of https://support.hp.com/us-en/document/c01857696
