The most hit pages on this blog are the CPU Temperature Guides, so here is a comprehensive(work in progress) guide to everything(almost) related to CPU Overheating.
Symptoms of a Overheating CPU :
1. Random Crashes:
Your system may switch off or restart automatically while you are using it. And this may happen repeatedly. If the overheating problem is not severe enough, then your PC may only crash when you are running many CPU intensive applications or running a CPU intensive game. If your CPU temperature is very high, then the system may restart as it is booting up ending into a endless and dangerous loop.
An overheating CPU underperforms, result being a sluggish computing experience. The system may experience random lock-ups too.
A PC may also crash due to RAM, Motherboard, Hard Disk & Power Supply Unit issues.
Causes of CPU Overheating:
1. Improper CPU + Heatsink installation:
If your system is new and you have overheating issues, or if you have recently installed a new CPU/heatsink or if you have fiddled with the system and have removed and replaced the heatsink, improper contact between the CPU & heatsink could be the likeliest problem for CPU overheating. A thermal grease or pad exists between the CPU and heatsink. Properly applied thermal grease ensures proper thermal contact and proper dissipation of the heat that the CPU generates. Improperly applied thermal grease could make heat dissipation inefficient and thus cause the CPU to overheat.
2. CPU fan malfunction:
Most desktop environments have an active heatsink (i.e. heatsink with a fan). A CPU fan may malfunction due to dust, a faulty fan or a faulty power supply.
3. Airflow and Case related issues:
Proper airflow in the case is essential for the life of your computer. Dust clogging up the escape points in your case can impede airflow and increase operating temperatures. An uncleaned case may act as a completely sealed case which will shorten your computer's life. Some cases have a side fan and a malfunctioning side fan can add to your temperature woes. Check the heatsink, it might be clogged with dust "bunnies".
Though a CPU's temperature will rise when processing demands rise, a CPU should not overheat in such conditions.
Solutions to an Overheating CPU:
Solutions will depend on the cause of an overheating CPU.
1. Improper CPU + Heatsink Installation:
Solution would be to unseat and reseat the CPU heatsink properly, reapplying the thermal compound
in the process. This can be risky and if improperly done could fry your CPU.
CPU lapping: (CPU lapping will void your warranty. Not recommended and proceed at your own risk.)This involves sandpapering away the surfaces of the CPU and/or heatsink, so as to achieve more surface to surface contact between the CPU and the heatsink.
2. CPU fan malfunction:
If the problem is dust collected between the fan blades, air dusting it might solve the problem. Be wary and careful while using a lubricant on a recently purchased fan, chances are you may not need it. If the fan still refuses to spin , ordering a new fan might be the only solution. While ordering a new fan you might consider heavy duty cooling fans like Cooler Master or try another cpu fan.
3. Airflow and case issues.:
There's almost nothing that a good dusting does not get rid off, when it comes to airflow issues in a case which functioned well when new. Regular dusting with compressed air is a good idea. If a cpu case fan is not working, you may want to replace it.
Apart from aircooling the CPU with CPU fans, heavyduty users might want to look at liquid cooling options available.