ATI Radeon HD 3870 and 3850: 55nm RV670

Before we bring this article to a close, we'd like to cover a few final data points. Throughout all of our benchmarking and testing, we monitored how much power our test system was consuming using a power meter and also took some notes regarding its noise output. Our goal was to give you all an idea as to how much power each configuration used and to explain how loud the configurations were under load. Please keep in mind that we were testing total system power consumption at the outlet here, not just the power being drawn by the video cards alone.
  

Total System Power Consumption & Acoustics It's All About the Watts and Decibels

While idling and under load, the new Radeon HD 3970 and 3850 cards consumed significnatly less power than all but the entry level Radeon HD 2600 XT and GeForce 8600 GTS cards.  The design changes and move to a 55nm process paid huge dividens in terms of power consumption.  Keep in mind, the Radeon HD 3870 performs on par with the Radeon HD 2900 XT and GeForce 8800 GTS, while using less power.  That makes the Radeon HD 38x0 series a winner in the performance-per-watt department.  What a difference a few months can make.

In terms of noise output, we're happy to report the new Radeons were barely audible over the noise produced by our test system's CPU cooler, PSU fans, and hard drive.  During normal operation, these cards are significantly quieter than the Radeon HD 2900 XT and are on par with or quieter than NVIDIA's offerings.