As one of the most complex components in a computer system, the video graphics array (VGA) card is also among the hottest when in use. Upgrading the VGA heatsink can result in better overall airflow within the system and can provide additional stability. When you are picking a cooling unit for a VGA card, price, noise and the amount of available space should be the most important factors. Professional and customer reviews can give great indications of what kind of problems and successes other users have had with a given VGA heatsink.
Heatsinks are common in electronics. Complex semiconductor chips can be destroyed by the heat that they generate, and heatsinks are designed to remove heat from them. They are made out of materials that conduct heat well and have large surface areas that allow heat to radiate. A heatsink is often combined with a fan, which is referred to as "active cooling" and further improves performance by passing cooler air over its surface. Ideally, a VGA cooler will provide heatsinks not only for the graphics processing unit, but for the video memory as well.
When choosing a VGA heatsink, it is important to consider how much room is available in the computer's case. Some VGA cooling devices are dual-slot designs, meaning that they are so wide that they occupy the motherboard slot that the video card is in and the slot next to it as well. Some heatsinks even use three case slots and provide the option of adding fans that take up two more slots.
The advantage of dual-slot designs, aside from increased heat dissipation and air circulation because of their sheer size, is that the second slot is usually used to expel hot air from the system as exhaust. This helps keep the central processing unit (CPU) and other components cool. Not every motherboard layout is going to allow space for a double-width VGA heatsink, however, especially when two video cards are used in combination. Before selecting a unit of this type, it is important to be sure that it will actually fit inside the case.
Video card cooling units tend to be among a computer's loudest components, and improved performance often comes at the cost of added noise. If using a low- to mid-range video card, cooling units are available that use several heatpipes to transfer the heat to a large heatsink. These use slow, quiet fans — or sometimes are passive units with no fans at all — and typically provide a means of controlling the fan speed. Units of this type are generally not powerful enough to handle the increased cooling requirements of a high-end video card. For these, the preferred solution is one that pumps water through a cooling block attached to the VGA card.
Cost is another consideration. Although VGA heatsinks are moderately priced, you might prefer to spend the money on a better video card instead. The decision is further complicated by the fact that many of these coolers are designed for a specific video card layout. That expensive cooler might not be reusable should you later buy a card from a different manufacturer or even a card of a different series from the same manufacturer.