Noise, Temperature & Power
Noise
The graph represents measurements taken two inches from the card's I/O bracket. You might consider these numbers to be rather quiet, but to my ears they seemed much louder. My suspicions were confirmed when I moved the meter next to the fans instead. Two inches away from them, my instrument returned a much different result.
Directly behind the card, the meter registered 43 dB(A). That's not particularly loud, but this isn't the quietest card we've tested, either. The reading taken in front of the fans is quite a bit louder, registering 51 dB(A). That's after 10 minutes of game play; at idle, the card is completely silent since its fans don't spin at all.
Temperature
Temperature measurements are taken over 10 minutes using GPU-Z in a 25-degree room. As you can see, the Tri-X cooler mounted to the R9 390 keeps AMD's Hawaii GPU cooler than the R9 Fury, despite having fewer heat pipes than the Fury.
Sapphire’s R9 390 Nitro peaked at 70 degrees after almost eight minutes in Battlefield 4. This was in an open test bench with no fans, though. In a case with proper circulation, the temperature probably wouldn't reach as high.
Power
The power consumption test that I perform takes measurements at three different times. Power draw is measured while the system is idle, at the end of a 10-minute Battlefield 4 run before quitting and while FurMark is being run.
Sapphire’s Radeon R9 390 Nitro is far from an energy efficient graphics card. At idle, it pulls 16.7W, even though its fans aren’t usually spinning. Gaming is where you'll really see the big power numbers though. It draws as much as 255W in Battlefield 4, which is nearly 85W more than the similarly-priced GTX 970 and 70W more than the comparatively powerful GTX 980. For some reason, FurMark affects AMD's GPUs more than Nvidia's. The R9 390 Nitro needs as much as 323.3W in this test.