Noise annoys

System: Intel Core 2 Duo, MSI 975X Platinum motherboard, Windows 7 Home Premium

Q: My PC was built for me by a friend and has been fine for the past year or so. However, recently the CPU fan has become very noisy, making a ticking, rattling sound as the machine is running. I think it might need replacing but unfortunately the friend who built the system has moved away. Is this something I could undertake myself or would I be better taking the machine to a specialist?

A: The first thing to do is take the side off the case and have a look at what’s happening inside when the system is running. The standard cooler supplied with retail Core 2 Duo chips has relatively exposed fan blades and it may be that they’re simply catching on a stray wire inside the case which is causing the noise.

If this isn’t the case, then replacing the heatsink/fan assembly isn’t a difficult task provided you take care. Make sure you take antistatic precautions by touching a radiator or other earthed object before you start. On modern Intel CPU systems the cooler is held in place by four plastic studs that locate in holes in the motherboard. These are pressed down and twisted to lock them into place. Unplug the fan’s power cable from the motherboard header, release the clips by pressing and twisting anti-clockwise and you should be able to lift the old cooler off.

In order to ensure good heat conduction from the chip to the heatsink thermal paste is used. You need to clean off any residue of old paste from the top of the chip. Use a tissue moistened with a little white spirit.

You can buy a new cooler for about £5, but we’d recommend spending £10 or £15 to get a good quality unit – if it uses an aluminium heatsink make sure it has a copper insert. You’ll often find that thermal paste is pre-applied to the cooler, check when buying, otherwise you’ll need to spend a few more pounds to buy a tube.

Refitting is a reverse of removal. Apply a thin layer of paste – if required – seat the new heatsink on top of the chip, press down the pins and twist clockwise to lock them into place. Connect the fan’s power cable to the motherboard header and you’re ready to go.

Coolers for modern Intel CPUs are held in place by four plastic studs that latch into holes in the motherboard