Power ConsumptionCooling modern video cards is becoming more and more difficult, especially when users are asking for quiet cooling solutions. That's why the engineers are now paying much more attention to power consumption of new video card designs.
|CPU:||Intel Core 2 Duo E8400 @ 3.6 GHz|
(Wolfdale, 6144 KB Cache)
|Memory:||2x 1024MB A.DATA DDR2 1066+ CL4|
|Harddisk:||WD Raptor 740ADFD 74 GB|
|Power Supply:||OCZ GameXStream 700W|
|Software:||Windows XP SP2|
In order to characterize a video card's power consumption, the whole system's mains power draw was measured. This means that these numbers include CPU, Memory, HDD, Video card and PSU inefficiency.
The three result values are as following:
- Idle: Windows sitting at the desktop (1024x768 32-bit) all windows closed, drivers installed.
- Average: 3DMark03 Nature at 1280x1024, 6xAA, 16xAF. This results in the highest power consumption. Average of all readings (two per second) while the test was rendering (no title screen).
- Peak: 3DMark03 Nature at 1280x1024, 6xAA, 16xAF. This results in the highest power consumption. Highest single reading
The difference in idle, is because AMD uses a lower idle clock frequency than PowerColor. The GPU will sense its current load state (independent if it's running 2D or 3D) and adjust clocks according to a profile stored in the BIOS.
The load and peak differences are because of the different shader count on these two cards, for more details see page 1.