At 1440p, R9 390 can hit 50-60 fps on pretty much everything at ultra, just without antialiasing, less ambient occlusion and turned down shadows. It is clear that the R9 390 is a significantly more capable high-end card that can play AAA titles at 1080p/1440p with 50-60 frames per second. It is worth noting that the R9 390 is a very power hungry card and requires a decent power supply unit. In terms of memory, the R9 390 's 8192 MB RAM is more than enough for modern games and should not cause any bottlenecks.
Conclusion. In the end, drawing a sweeping conclusion is difficult when there's no actual reference graphics card. The next best approach is evaluating cards from AMD's partners.
The R9 390 is AMD's rival to the Nvidia GTX 970 that's ideal for 1440p gaming, but it draws a lot of power for the performance you get.
AMD is pleased to bring you the new R9 390 series which has been in development for a little over a year now. To clarify, the new R9 390 comes standard with 8GB of GDDR5 memory and outpaces the 290X.