Is Airflow Essential?
The SCS3 is marketed as a zero-noise solution, so naturally, some users will be contemplating the idea of using the card in a completely passive build. However, as depicted by the above graph, airflow is essential in keeping the PowerColor card running smoothly.
The blue curve shows GPU temperature throughout a 10-minute run of Far Cry 3 with the Graphite 600T fans enabled, while the red curve plots temperature with all the chassis fans disabled. In the latter scenario, the CPU and PSU fans are still running, but the PowerColor card is clearly starved of air and the heatsink is unable to perform efficiently - temperature rises quickly and soon hits 100ºC, which produces another unwanted side effect...
Examining core clock speed during the same benchmark revealed that the SCS3 was unable to maintain top performance without chassis airflow. As the card reaches 100ºC, the GPU automatically throttles to 450MHz in an effort to keep temperature in check, hence the sawtooth effect in the above graph. There are no such problems when the SCS3 HD7850 has a steady supply of air - it still runs hot and can go beyond 90ºC, but it's less likely to run into performance limitations.
