Support for AMD FreeSync
Supports AMD Virtual Super Resolution and Framerate Target Control
No HDMI 2.0 support
Average clock speed well below advertised 1000 MHz
Fan doesn't turn off in idle
I see the R9 Nano as the optimum choice for 2560x1440p gaming, with most titles being well playable at 4K if you turn off AA and are willing to reduce settings a little bit.
For 1080p, the card seems to be overkill, especially due to its high price. Averaged over our test suite, we see the R9 Nano 10% faster than the R9 390X, just 3% slower than the R9 Fury, and 13% slower than the R9 Fury X at 4K. This means the card is 10% faster than the GTX 980 and 14% slower than the GTX 980 Ti. But all this doesn't matter if you need a compact card as the R9 Nano is the fastest choice with such a form factor.
In addition to the AMD review sample, we purchased a retail Sapphire R9 Nano, which is the exact same card in terms of components, PCB design, and specifications. Due to AMD's approach to frequency selection, each card will perform slightly differently because each board's heat output is slightly different, which will change the selection of clocks to stay within the power limit. Between both our samples, we see the AMD reference board in the lead consistently with roughly a 1% performance advantage. While this is new for AMD, NVIDIA cards have behaved like this for years.
Once you cram the card into a small case with limited airflow, the cooler will ramp up to keep temperatures in check, resulting in a somewhat noisy 41 dBA, which is definitely not something you'd want in your living room. What really turns me off is the massive coil whine on the AMD sample; we recorded it for you in our video on page 35. No matter the FPS, you will always hear an electrical chirping that will change in volume and frequency depending on the game's scene, which makes it even more pronounced. I wonder how their engineers missed this again (remember the HD 7990?).