Total System Power Consumption
Before bringing this article to a close, we'd like to cover a few final data points--namely power consumption and noise. Throughout all of our benchmarking and testing, we monitored how much power our test system was consuming using a power meter. Our goal was to give you all an idea as to how much power each configuration used while idling and while under a heavy workload. Please keep in mind that we were testing total system power consumption at the outlet here, not just the power being drawn by the graphics cards alone.
This is a significant chart, for a variety of reasons. First and foremost, the GeForce GTX 480's power consumption while under load is extremely high for a single-GPU powered card. At 438 watts under load, the GeForce GTX 480 consumed almost 40 more watts than the dual-GPU powered Radeon HD 5970, despite offering lower performance. With regard to power efficiency, it is obvious, the GF100 GPU is significantly less efficient than the Radeon HD 5870.
With power consumption this high, it should come as no surprise that the GeForce GTX 480 also runs relatively hot, with the added side effect of a relatively loud cooler. Under load condition, we witnessed GPU temperatures in the mid to high 90'C range and even witnessed temperatures on the backside of the card hit 78'C (as tested with an infrared thermometer).
To dissipate the heat generated by the GF100, the GeForce GTX 480 is outfitted with a large cooler, with a barrel-type fan. Under idle conditions, while sitting at the desktop, we found the GTX 480's cooler to be nice and quiet. Under load, however, the fans spins up significantly and can be somewhat loud. A GeForce FX 5800 the card is not, but the GeForce GTX 480 is clearly the loudest GeForce to hit the scene in a number of years.