It appears that AMD's next-gen Radeon R9 390X is already up and running as it was spotted at GDC 2015 but apparently AMD will not launch it until Computex 2015 show scheduled for June.
According to
PC Perspective's Ryan Shrout, AMD was running Oculus Rift demo at GDC 2015 on its next-gen graphics card, presumably the Radeon R9 390X. And while we do not have any pictures to confirm it, Ryan was told that the demo was running on the "upcoming flagship Radeon R9 video card."
While it was happily running at GDC 2015, it appears that the new R9 390X will have to wait for Computex 2015 show in June. According to
a report from KitGuru.net, AMD will launch it full Radeon 300 series during Computex 2015. AMD might also announce it Radeon 300 series lineup prior to the show, but these will be available after the show.
AMD might move its schedule a bit now that Nvidia has officially unveiled its newest flagship Titan X graphics card but might also wait to see what has Nvidia prepared after we see some official specifications during Nvidia's GPU Technology Conference.
Source:
Tweaktown.com.