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.
In such an energy aware climate, AMD are making a big deal out of their new ‘ZeroCore Power’ technology. Many solutions today use power gating, clock gating and memory compression to reduce idle power requirements, but ZeroCore power technology can completely power down the core GPU while the rest of the system remains active.
All of these cards are power hungry high end models, although the Asus Matrix HD7970 Platinum consumes less power under load than both the HIS 7970 X Turbo IceQ X2 and the Sapphire HD7970 6GB Toxic when Lethal Boost is enabled.