CPU fans creates sound at startup

[Chitamacha]

I have problem with the fans for CPU. Whenever I press the power button on it then it starts to create noise and as I login to the system then it stops creating that noise. This is happening to me from last one week. I am afraid that it can damage something in my computer. I have never opened my computer cabinet. Please tell me that what should I do to make it silent.

[mathews]

I think that the motor is failed to start and that is why it is creating the noise. When your computer reaches to the normal operating temperature then it get quiet. This happens when the metal parts of the motor get heated. My suggestion to you is to get a new CPU fan for your computer and replace the existing one. This is very important because it plays a major roll to make the CPU cool and if it is faulty then your CPU may also get damaged. So change it as soon as possible.

[Aandaleeb]

This seems that the ball bearing is gone. Are you sure that this is the fan on your CPU. It can also be the fan that is there on your graphic card. To come out of this confusion, your should open the case when it is creating noise and put your figure on fan and see whether it stops making noise. If it stops making that noise then this will confirm that the problem is with that fan and you can move for the solution accordingly.

[Filiberto]

There is more possibility that there something is coming in the path of the fan and that is creating that sound. If that is the case then you need not to do anything. Just open the cabinet and check for any wire that is coming in the fans path. Set the wires properly and start the computer. This should not show you problems again.