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.
Power consumption is very impressive, draining only 8 watts when idle. When gaming, this rises to around 40 watts, and 56 watts when under Furmark load. A very conservative card indeed.