Thinkpad X120e unusual fan noise

[Degru]

I have had my X120e for a while now and am happy with it. The normal fan noise has not bothered me, but lately I have been hearing some strange noises from the fan when I hold the laptop at an angle. 

If I start slowly turning it onto its right side, I hear a noise from the fan that sounds a little like the fan is catching on something inside. This noise stops after two seconds, but resumes as I continue to turn the laptop. I have already opened it up and tried blowing into the fan, dislodging some dust, but it still makes the noise sometimes. The laptop continues to function normally when I hear this noise.

What could be causing this? Is it something I should worry about?

Thank you in advance.

[cche0691]

Hi Degru,

  Please try BIOS update. If problem persist after BIOS update, please kindly contact local Lenovo for hardware test.

BIOS Update Utility for Windows 7 (32-bit, 64-bit), Vista (32-bit), XP - ThinkPad X120e
http://support.lenovo.com/en_US/downloads/detail.page?DocID=DS013661

Fred

[Degru · Accepted solution]

Oh, I've fixed it. The fan's power cables were a little too close to the fan blades, and the fan would sometimes catch on them. I just pried them a little bit away and it has stopped making the sound.