Does heat sink compound degrade with time?

Does heat sink compound degrade with time? How long isv it recommended before I replace my CPU heat sink compound?

I have a DELL Studio 17" notebook with core i7 from the lastv one and av half years and it is making more fan noise now than when it was new. Is it time to clean up the heat sink and reapply the paste?

Solution 1:

The compound can degrade with time, but more common is a phenomenon known as 'thermal pump out' - over time, with cycling of the CPU die from running hot to powered off and cold, the compound tends to migrate away from the centre towards the edges. This problem has been reduced somewhat with modern processors with integrated heat spreaders (the metal cap over the die), but not completely eliminated - and many laptop processors skip the heat spreader to save space.

You should get a few years from typical use with a good compound, but it's still worthwhile taking the time to ensure the heat sink is free of dust and other contamination before your symptoms turn from fan noise to random lockups - if you're not concerned about your warranty (and it hasn't expired) then there's no harm in cleaning the CPU & GPU, and the heatsink, and reapplying a new layer of compound. Just be sure to apply evenly and sparingly - you're looking for a layer less than a half millimetre thick with no missing spots.