Power, Temp and Noise
That's a surprise, but we re-ran the benchmark and can confirm the result. The R9 290X DirectCU II OC's core and memory overclock makes the card noticeably more power-hungry than AMD's reference design, and system-wide power consumption is pushed to 360W.
That's interesting, too. We were expecting to see the DirectCU II tame AMD's hot-running GPU, but when used in its out-of-the-box state the under-load temperature is practically identical to the reference board.
There's a reason for that. Remember, Asus's board has a BIOS switch that allows the user to toggle between quiet and performance modes. Switching to the latter and re-running the temperature test returned a more-comfortable reading of 84ºC, though, that extra cooling performance comes at the expense of noise...
With the Asus card set to BIOS 1 (quiet), the fans ramp up to 1,500rpm and system noise was measured at 40.5dB. Not the quietest by any means, yet switch to BIOS 2 (performance) and the fans ramp up to 1,900rpm, causing noise levels to further increase to 43.1dB.
And there's more to this BIOS switch than first meets the eye. Our logs reveal that the card quickly becomes performance-limited when set to the quiet profile: after a couple of minutes the hike in temperature causes the GPU to throttle and deviate from the specified 1,050MHz. Switch to BIOS 2 and it's able to run at a sustained 1,050MHz for much longer periods.
It's always nice to have the option, but that's a compromise we weren't expecting to have to make in a premium enthusiast card.