Power Consumption: A Detailed Look At Gaming And Stress Testing
Gaming Power Consumption
Two things jump out when we compare PowerColor's Devil 13 to AMD's reference Radeon R9 295X2. First, PowerColor manages to limit the peaks in power consumption so that they’re barely above the average. Even though the Devil 13's PowerTune-based jumps are a bit more pronounced than the reference card, its sophisticated power supply smooths out the extreme peaks, relieving pressure on the PSU.
Second, it’s very noticeable that PowerColor uses the motherboard's 3.3 V rail to take care of components like the Devil 13's GDDR5 memory, whereas the reference card stays exclusive to 12 V.
Both solutions are very different. But PowerColor comes out ahead in the end. Our measurements also show that the two graphics cards have roughly the same ratio of power draw to performance. In the Devil 13's case, that means we observe lower consumption corresponding to slightly less speed.
Again, a direct comparison shows some differences. Even though the Devil 13 manages to sustain its clock rate in every scenario, some kind of measurable voltage clipping limits the maximum power draw to an average of 409 W (power target), which is barely higher than our gaming benchmark.
Lower compute-based stress test results confirm our findings. The power-to-performance ratio holds steady, which exposes the tricks used to avoid pushing this three-slot air cooler past its limits. Even though AMD sets a power target of 208 W per GPU (and sticks to it exactly with the Radeon R9 295X2), PowerColor's Devil 13 stays below that number.
Looking at the 12 V power supply through the four eight-pin PCIe connectors, the Devil 13's smoother curve is noticeable yet again. This consistent power draw is different from AMD’s reference design, which has been known to push PSUs beyond their limits. Certain supplies that weren't able to properly support AMD's Radeon R9 295X2 due to its peak power draw have no problem with PowerColor's board.
As for the 3.3 V rail through the motherboard slot, it's the same here as it was during our gaming workload. The wheel doesn't need to be reinvented.