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 graphics 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 measure the power consumption of only 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 is used for all measurements. Again, these values only reflect the card's power consumption as measured at its DC inputs, not that of the whole system.
We use Metro: Last Light as a standard test for 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; 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.
Our results are based on the following tests:
- Idle: Windows 10 sitting at the desktop (1920x1080) with all windows closed and drivers installed. The card is left to warm up in idle mode until power draw is stable.
- Multi-monitor: Two monitors are connected to the tested card, and both use different display timings. Windows 10 is sitting at the desktop (1920x1080+1280x1024) with all windows closed and drivers installed. The card is left to warm up in idle mode until power draw is stable. When using two identical monitors with the same timings and resolution, power consumption will be lower. Our 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 15 Ultra is used at a resolution of 1920x1080 to play back the Batman: The Dark Knight Blu-ray disc with GPU acceleration turned on. Measurements start around timecode 1:19, which has the highest data rates on the BD with up to 40 Mb/s. Playback keeps running until power draw converges to a stable value.
- Average: Metro: Last Light at 1920x1080 because it is representative of a typical gaming power draw. The average of all readings (12 per second) while the benchmark was rendering (no title/loading screen) is used. In order to heat up the card, the benchmark is run once without measuring power consumption.
- Peak: Metro: We use Last Light at 1920x1080 as it produces power draw typical to gaming. The highest single reading during the test is used.
- Maximum: We use Furmark Stability Test at 1280x1024, 0xAA. This results in a very high no-game power-consumption reading that can typically only be reached with stress-testing applications. We report the highest single reading after a short startup period. Initial bursts during startup are not included as they are too short to be relevant.
Power consumption results of other cards on this page are measurements of the respective reference design.
Moving from the 28 nanometer process to 14 nm FinFET provides significant power improvements; AMD also reports that they have implemented additional efficiency improvements in their new architecture.
Gaming power draw is definitely improved over the last generation, even though the RX 480 uses GDDR5 memory which is not nearly as power efficient as HBM. Polaris can't beat NVIDIA's current Pascal lineup in efficiency, but we see numbers similar to NVIDIA's last generation (GTX 970, GTX 980); performance is similar too, and so is performance per watt.
The picture is completely different in non-gaming states, though; here, it looks as though AMD still hasn't learned its lesson. Single-monitor, idle-power draw with 15 W is just ok I guess, but multi-monitor and Blu-ray using more than 5x as much power as NVIDIA's counterparts is simply unacceptable, especially since this has not been addressed for several years.
Furmark maximum power caps out at 166 W, which is higher than the board's power input configuration (150 W). Normal gaming is higher than that limit, too. While nearly all motherboards and power supplies should be able to handle that, it still exceeds specifications, especially if you crank the power limit up while overclocking. Two 6-pin or one 8-pin would have maybe been the better power configuration.