What Happens to a CPU When the Fan Dies?
A CPU’s operating temperature will rise if the cooling fan breaks, dramatically increasing the chance of hardware failure. Stock modern computer CPUs use a two-part CPU cooler that features a heatsink directly connected to the CPU and a fan that cools the heatsink. The fan’s role is secondary, but it is of vital importance in preventing the CPU from overheating: the heatsink will not dissipate heat fast enough to prevent damage to the CPU without an operational fan.
CPUs with dead fans will overheat. Computers usually have built-in safe guards to shut down or slow down the CPU when it gets too hot to prevent it from breaking. However, if the computer’s safeguards fail or don’t kick in fast enough the CPU can get above its maximum operating temperature and literally burn out. The CPU can get so hot it will ignite, destroying itself beyond repair. A fried CPU can also take down the motherboard and other connected components with it when it goes. The CPU will break if the computer is continually used with a dead CPU cooler fan.
When the Fan Dies
If the CPU fan fails, shut down the computer immediately to prevent hardware damage. Running a normal system shut down may not be fast enough: in this instance it can be safer to shut down via holding the power button or pulling the plug. Hard shutdowns run the risk of damaging data, but leaving the system on even just a little longer to shut down via normal methods runs a high risk of destroying the computer.
Intel and AMD Defense Mechanisms
Intel and AMD CPUs will produce error messages and try to shut down if the CPU fain fails. Intel CPUs will drop the CPU’s clock speed to prevent it from going above its operating temperature range. These CPU defense mechanisms are designed to prevent the computer from breaking in the event of CPU cooling failure. If you turn the computer back on, it will display an error message and cut power in a few seconds to prevent CPU damage. Repeatedly trying to power on the system again can damage the CPU as the CPU can get above its maximum operating temperature in seconds without sufficient cooling.
A dead CPU cooling fan should be replaced immediately after failure and the computer should not be used again until a functional cooling unit is installed. It’s typical to replace the entire cooling unit when the fan fails. Additionally, the thermal cooling compound that bridges the physical connection between the heat sink and the CPU needs to be replaced when installing a new cooling unit. You can install the new unit yourself or bring it to a professional: incorrect cooling unit installation can also break the CPU. A CPU that’s powered on without cooling or poorly installed cooling can ignite in seconds.