To test power consumption today we are using a Keithley Integra unit and we measure power consumption from the VGA card inputs, not the system wide drain. We measure results while gaming in Crysis Warhead and record the results.
The heat and noise dynamics make sense when we see the power consumption results. The HD6670 is a power sipping miser which consumes only 8 watts when idle and 47 watts when gaming. The HD6770 couldn’t be classed as a power draining monster either, but it does consume almost double the power when gaming … around 91 watts in total.