Shoutbox

Although it can be dust/dirt, or a background program which continuesly demands a lot of CPU power, it often is a problem with the cooling plates.

Because of their small component size, laptops often rely heavily on cooling plates in addition to a fan. This because there isn't enough space to have a good air circulation inside the casing. Therefor, the fan is quite often 'only' used to cool the cooling plates and not for cooling the components directly. The heat from those plates is redirected to the fan which on its turn tries to transfer it outside.

So, although it can be dust/dirt in the outlet of the fan, it often is a problem with the cooling plates and thus not so much with dust/dirt.

So I'd suggest to check all the cooling plates (or let it check). Check if they still come in good contact with the components they need to disperse the heat from. Check if, were needed, the special cooling paste/adhesive is still there. This is especially important for the CPU and graphics chips; the cooling plates need to be pasted or bolted on the chips. Even the tiniest space between the components and the plates causes hot air to build up, which is detected by the temp. sensor and thus the fan is instructed to run faster. A cooling plate only functions properly when it is directly on the component it needs to disperse the heat from.

Now, the more you 'travel' with your laptop (even picking it up and holding it in your hands counts as 'traveling') the more the casing distorts and the more chance there is the cooling plates gets distorted and thus they loose the extreme close contact with the components they need to cool.

This is quite often the number one problem concearning heating problems (except for broken or runout ball barings of fans; but if those are broken or runout you would hear a whole different sound, more like rathling, coming from your fan).

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Note: if you attempt to clean out your laptop yourself with a can of compressed air or do other hardware maintenance on it, take an extremely great care not to distort those plates. Even tighting a nut to strongly or 'unclicking' certain plates can distort them. And even a slight distortion of one millimiter can cause the plates to malfunction.

Also, using compressed air isn't always so good either. Spraying air also caused air friction, which on its turn can cause static electricity to build up. Especially laptops and their extremely small components are very sensitive to this. Also never ever touch chips directly or with a screwdriver or whatever (unless you know exactly what you're doing), this for the same static electricity problem.