Basics to System Cooling Continued:
 
F.  Make sure you have proper airflow. You need air flowing in at the front of the case near the bottom and exhausting out the rear of the case up at the back. Added fans are a good start. It is also important to make sure you have all the side and top panels installed, leaving panels off disrupts airflow and increases the chances that a dead air space where heat can build up will develop. Next, make sure the airflow is not blocked. Try tying the cables and cords out of the way; if you have to, consider getting rounded cables. The entire goal is to move and remove as much of the cables that may cover the motherboard as possible. You want to maintain as much open space over the motherboard as possible so cool air can get from outside the case into the case - cool the components - and exit as warm air out the rear of the case. 

G. The things you can do to your computer itself are more important than changing its environment. A coating of dust insulates your electronic parts and aggravates whatever heat problems you may have, the more dust you have in your system's components, the worse heat issues you will experience. You have to keep everything clean with regular maintenance. The Power Supply probably accumulates the most dust. A vacuum hose and/or compressed air is the only way to dislodge the higher percentage of dust trapped in the PSU and other components in your case.  
 
H. Be sure to add or upgrade fans. Your case may have mounts ready for optional fans and 80mm-120mm fans cab be purchased at reasonable prices. Many motherboards now let you check your CPU temperature. If your CPU is overheating, upgrading your CPU cooler (heatsink with fan) may be important. Another fan location often overlooked, yet one of importance, is the hard drive fan, an intake fan that draws cooler air in and blows it over the hard drives. Another option is to add a slot mounted fan to better cool the video card. These usually mount in the slot right next to the card, but there are also other types that can add directed airflow to parts of the case.

I. Cases: Case size is another important component that plays a significant role in the thermal properties of any system. In addition to providing room for expansion - components and large cases typically allow for better cooling since more air is circulating throughout the case. A good case should allow for both intake and exhaust fans to be installed. In a typical desktop tower form factor, air should flow in from the bottom front of the case and exhaust out the top rear of the case. The ambient air temperatures inside the case will play a large role in the effectiveness of individual solutions used for the processor, the video card and the chipset. Therefore, expelling excess heat is essential for proper cooling and stability.

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