Enthusiast grade gaming video cards have long used dual slot coolers in order to cope with upwards of 200W of power. Dual GPU cards require even more power which adds to the thermal load.
In recent years following forum posts and and returned cards galore, the industry now has began using more sophisticated coolers that run cooler and and quieter.
card we acquired with a factory made dual fan cooler was the EVGA GTX 660 Ti FTW Signature 2. EVGA has began using dual fans on their enthusiast cards. We noticed a solid improvement in the operating temperature as well as improved acoustics.
We also have a Sapphire HD 6970 that originally came with a single fan cooler, but it was retrofitted with an aftermarket 3-fan cooler which provided much less noise under load.
For manufacturers, the cooler operating temperatures reduce the problems of thermal failure. At higher temperatures, thermal interface material can degrade causing the card to activate a thermal shutdown. Warranty claims are very expensive.
Our old EVGA GTX 260 SC ran hot mostly because it was factory overclocked. Furmark could heat the card to 95°C which is close to the thermal limit. The dual fan EVG GTX 660 Ti was much cooler at 75°C even with the card factory overclocked.
The triple fan cooler is even more effective, our HD 6970 was stable at 67°C after 20 minutes of burn-in. The Arctic Accelero Xtreme III cooler needs 3 slots and it’s 29.5cm long. The cooler uses thermal epoxy for the RAM heat sinks which work more effectively then the conventional coolers can. Replacement fans are also inexpensive.
We have looked closely at the top model cards from all manufactures which have made many advances in cooler designs. The EVGA cooler fits a dual slot rig easily and it remains short enough for older ATX chassis. Gigabyte has some triple slot models that provide extreme cooling. The industry is largely adopting the 2 slot dual fan design across the line; EVGA and Sapphire etc. now widely use dual fan coolers.
Generally flagship video cards are the most power hungry. The thermal load has come down somewhat as semiconductor sizes fall but flagship cards have continued to use as much power as possible. The HD 7970 uses almost as much power at 28nm as our HD 6970 does at 40nm. The GTX 660 Ti uses about 75% of the power of the older GTX 260.
We are using a Corsair Carbide 300R chassis, which is a standard mid-tower design. Its rich with fan bays for the most demanding requirements. Given that Radeon cards use upwards of 250W, we installed a pair of fans on the top to augment the air flow. Working with the rear fan, the top fans move vast amounts of air to effectively remove heat out of the machine.
Furmark has long been a popular choice for benchmarking but its more practical when dealing with demanding loads.