Overheating Problems

Blocked CPU heatsinks can lead to severe overheating ...

Over the years of repairing PC desktops and laptops I have found some good examples of totally choked CPU heatsinks which can lead to CPUs running 20 deg C hotter than desirable. CPUs these days do not "burn out" but rather reduce their work load to keep their temperature within their upper limit which maybe a high as 75 deg C. Below are some photos of particularly bad examples! You can click on the pictures to take a closer look!

The first two show what can happen to a laptop exhaust port when too much fluff builds up on the heatsink fins. Left is the dismantled laptop and right is a closeup of the blocked heatsink.

These two examples are typical of totally blocked desktop heatsinks. Both resulted in CPUs running about 20 deg C hotter than normal which resulted in load shedding and a very slow PC!


Left is the typical condition of a 3 - 4 year old desktop PC that has never had its CPU heatsink cleaned! (Apologies for the slightly out of focus photo but it was such a good example!)

It is a good idea to keep desktop towers of the floor particularly if it is carpet. If the tower has to sit on carpet then try not to use a vacuum in the room when the PC is running as the PC fan draws air in at the front with any dust and fluff that has been raised by the vacuum head.

Whilst you can certainly look inside a desktop tower case to check the condition of the CPU heatsink it is not recommended that you try and clean it unless you are confident that you know what you are doing!