Power Consumption & Temperatures
The R9 390X's peak consumption in BioShock matched the GTX Titan X as well as the R9 290X. The vanilla R9 390 system consumed 290 watts, which was virtually the same result as the R9 290 and GTX 780 Ti. Then we have the R9 380 which consumed less than the R9 280X and R9 285 but more than the GTX 960.
The power consumption margins in Metro Last Light are similar to what was seen in BioShock for the R9 390X and R9 390, as both matched the GPUs that they are replacing. The R9 380 was again 20 watts down on the R9 285 and R9 280X, and it was 40 watts up on the GTX 960.
The Tomb Raider system power consumption results tell the same story as those from BioShock and Metro.
Interestingly, compared to the R9 290X and R9 290 which peaked at a little over 80 degrees, the new HIS R9 300 series IceQ X² OC cards ran much cooler. Both the R9 390X and R9 390 models didn't even reach 70 degrees while the R9 380 peaked at just 56 degrees.