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. The best way to get maximum load results is by using Furmark, and even though it is not indicative of a real world situation it shows the limits the card can theoretically demand. The ‘gaming’ results are measured when playing Crysis Warhead and is a more valuable result to take from this.
As with all HD5000 Series based cards the power consumption of the PowerColor HD5770 Vortex is excellent. Consuming only 17W at idle and 66W when gaming in Crysis.Powercolor HD5770 Vortex 1GB Review,