If Performance Problem in Your Laptop or PC

Sometimes if your Laptop or PC happen like this :

"I've had this computer for about 2 years now and about 6 months ago, I began to have this problem. Every time I would run a graphics intensive game, the performance would gradually become worse and worse until it finally became unplayable. When it first started I would have about 30 minutes before the FPS rate began its sad decline. Today, it's less than 5.

Just yesterday, I tried a complete hard drive wipe with the hope that that would fix whatever the problem was but no such luck. My comp's running great now in every other regard. It loads up quick, basic programs have no delay, etc--but any game with decent graphics is still a disaster.

Does anyone know what might be causing this or what I might be able to do to fix it? "

answer what the problem is--Overheating.
- Explanation about overheating : The system is exhibiting behavior that suggests that there may be an overheating problem with a component, or with the system as a whole. Usually the symptoms that suggest this are heat that is noticeably felt inside the case or on a component, or erratic behavior such as system lockups.

- Diagnosis: Overheating is one of the main enemies of a reliable system. A PC that runs hot will have a shorter life span for its components, and at extremes of temperature, the possibility exists that the system will be unstable. It is even possible (though rare) for the overheating components to be damaged. The importance of system cooling is discussed in more detail here. One problem with diagnosing overheating problems is that symptoms can be related. For example, a processor overheating can lead to other components overheating; similarly, ventilation problems within the system case can exacerbate a problem cooling a processor that runs hot.

- Recommendation: Turn on the PC and run it for about an hour with the case on, in the way you normally would use it on a daily basis. Then perform the following checks:

1. Read this section in the System Care Guide on system cooling, and particularly on ventilation and air flow within the case. Consider taking some of the suggested steps to help you improve the ventilation inside the case if is not adequate.
2. Check the fan on the power supply to make sure it is running. This is the primary cooling mechanism for the PC case and if it is not working, the chances are good that something within the PC may be running too hot. If the fan has stopped, or if the volume of air it is moving seems low, troubleshoot it here.
3. Carefully touch the system processor, or the heat sink near where it attaches to the processor. If it feels so hot that you must withdraw your finger immediately, you likely have a processor cooling problem. Continue here.
4. Check the following components on the motherboard to see if they are running very hot: cache chips (or cache/COASt module), voltage regulator heat sink, BIOS chip. If any of these are running very hot and you are having problems with your motherboard, it may be bad. The voltage regulator can get very hot when some chips are used, and you may need to add extra cooling to keep it at operating temperature. The other components on the motherboard should not get very hot. If you are using a Cyrix 6x86 chip, make sure the motherboard is approved to use it or problems with overheating of the voltage regulator may result.
5. Check the system memory to make sure it is not overheating. It should be warm but not too hot to the touch. Overheated memory is a symptom of either bad memory or problems with the motherboard.
6. Check the hard disks' temperature as well. If they are running very hot then you may need to take corrective action.
7. If you are having repeated or continual heating problems within the case, you may want to consider moving your system into a larger case.

source : pc guide