Help! My PC Sounds Like a Blender! Annoying!

Factual Questions
1

Why does my PC sound like a blender? It makes a low-pitched “whirrrrr” sound which it never made before. There are rare periods when it even stops making the noise, but not for long. I WAG dust has built-up on the fan blades perhaps throwing the fan off-balance. Or, does the motor have a small bearing in need greasing? (I know, you’re thinking…look at your fan, stupid and see for yourself, but I’m temporarily disabled and it’s not so easy to maneuver to do so…meanwhile, the sound is driving me batty!)

Thanks,
Wounded Jinx

2

I have known the bearings on CPU fans to wear and begin ‘chattering’ - it can be quite serious, as this reduces efficiency/airflow and the CPU could overheat catastrophically.

Alternatively, it could be (as you say) something interfering with the fan blades of either the CPU fan (often the cables inside the machine can do this) or the one in the PSU (in which case it is most likely a bit of paper or something that has been sucked in).

3

You might check to see of any of the screws that hold the back/side of the CPU on have come loose and are vibrating.

4

The others are right that it is a fan, and determining which one is a little hard if you can’t open up the case.

Disclaimer - I’ve done this hundreds of times with no problems, but there’s always the first. YMMV.

To rule out your power supply fan, take something thin and slowly insert it into the power supply grill on the back of your PC. This will stop the fan (with a clunk!), but it will start up again right away once you remove the obstruction. If the noise stopped, you found the culprit! If not, it’s either another fan in your case, the CPU fan, or a video card fan (may not apply).

While you can repair old noisy fans in PC cases, it’s often more trouble than it’s worth. You can pick up new fans for under 10 dollars and install them yourself. If it is the CPU fan, don’t try to repair it and get a new one. That little fan only needs to fail for a minute and you have a dead PC, so it’s worth the money to get a new one.

Also, you might think about using a can of compressed air to blow out the dust. This can work temporarily, but I find that the dust is often just blow into the PC making things worse.

5

My PC used to sound like a bloody hedge trimmer, until I found www.quietpc.com
(well actually my dad [who owns an eerily quiet pc - you’d swear it wasn’ switched on] found it)

6

Possible sources for “whirring” noises from a PC:

  1. fan bearing
  2. something (like a wire) coming into contact with the fan blades
  3. Hi opal!
  4. a fan that is cracked or mechanically failing in some way
  5. hard drive bearing

I’ve seen fans get a lot of dust on them, but never so much that they get out of balance.

You’re going to need to open the bugger up and see where it’s coming from, unfortunately. If you are having trouble isolating the source, go down to ye ol local auto parts store and get about 2 feet of vacuum hose. Put one end to your ear and use the other end like a stethescope and you should be able to narrow in on the sound fairly quickly.