Power Consumption

Cooling modern video cards is becoming more and more difficult, especially with users asking for a quiet cooling solution, which is why engineers are now paying much more attention to the power consumption of new video-card designs. An optimized fan-profile is also one of the few things board vendors can create to impress with reference designs where they are prohibited from making changes to the thermal solution or components on the card.

For this test, we only measured the power consumption of the graphics card via the PCI-Express power connector(s) and PCI-Express bus slot. A Keithley Integra 2700 digital multimeter with 6.5-digit resolution was used for all measurements. Again, the values here only reflect the card's power consumption as measured at its DC inputs, not that of the whole system.

We chose Crysis 2 as a standard test representing typical 3D gaming usage because it offers the following: very high power draw; high repeatability; is a current game that is supported on all cards because of its DirectX 9 roots; drivers are actively tested and optimized for it; supports all multi-GPU configurations; test runs in a relatively short time and renders a non-static scene with variable complexity.

Power consumption results of other cards on this page are measurements of the respective reference design.

Our results were based on the following tests:

• Idle: Windows 7 Aero sitting at the desktop (1280x1024, 32-bit) with all windows closed and drivers installed. Card left to warm up in idle mode until power draw was stable.
• Multi-monitor: Two monitors connected to the tested card, both using different display timings. Windows 7 Aero sitting at the desktop (1920x1080+1280x1024 32-bit) with all windows closed and drivers installed. Card left to warm up in idle mode until power draw was stable. When using two identical monitors with same timing and resolution, power consumption will be lower. This test represents the usage model of many productivity users, who have one big screen and a small monitor on the side.
• Blu-ray Playback: Power DVD 9 Ultra was used at a resolution of 1920x1080 to play back the Batman: The Dark Knight disc with GPU acceleration turned on. Playback started around timecode 1:19, which has the highest data rates on the BD with up to 40 Mb/s. Playback was left running until power draw converged to a stable value.
• Average: Crysis 2 at 1920x1080, Extreme profile, representing a typical gaming power draw. Average of all readings (12 per second) while the benchmark was rendering (no title/loading screen).
• Peak: Crysis 2 at 1920x1080, Extreme profile, representing a typical gaming power draw. Highest single reading during the test.
• Maximum: Furmark Stability Test at 1280x1024, 0xAA. This results in a very high no-game power-consumption that can typically be reached only with stress-testing applications. The card was left running the stress test until power draw converged to a stable value.

A new GPU usually means improved power consumption numbers, but we don't see much of that here. Actually, non-gaming power consumption is yet again worse and ends up significantly worse than on anything NVIDIA has to offer at this time. I am especially shocked by multi-monitor and Blu-ray power consumption.

During gaming, we see high numbers that are among the highest we've ever seen. I do have to admit that performance of the card is very high, too, yet the card still falls behind every other card except the HD 7970 GHz Edition in performance per watt.

Furmark maximum power is well below the 375 W that the PCIe power input configuration is specified for, but I saw short sub-second spikes above 400 W right as Furmark was started. These spikes were very short, shorter than what would matter to even an underpowered PSU, which is why I won't use them in this case.