Well.. as far as I know, there will be no RX 490, it was canceled from what I was told. The RX 590 will be it's replacement, aka Vega that is GCN 5.0 based and will have 16GB HBM2.
Unless..that may have changed? Could be I guess.
Oh wells my bad news is that my R9 290X died just after the lilifetime warranty

And I must admit that the hardware quality no matter if it's a GeForce or a Radeon is disappointing these days, all this Made in China garbage, low quality solder etc, I never had a single Radeon or GeForce or Vodooo die on me as they were all made in Mexico, Thailand, South Korea, Singapore & Taiwan for production units or Canada & USA as the Engineering Samples went.
For the games I play I am choosing the RX 480 8GB from Sapphire or MSI, these cost around 290 Euro's that to which is a sweet spot not even an NVIDIA card can compete with for that same value.
The RX 480 8GB will do me lots of good @ 1920x 1200 with Vulkan API, OpenGL Next & DX11. Since I mostly run Retro & mid gen games well the latest ones I do are only Fallout 4 and Primal Carnage: Extinction for the rest I am not so bothered really.
GTA 5 seemed fun, but ergh not kinda of planning on spending so much money for a game, just not worth it.
The RX 480 8GB will do fine for X-Plane Global X Pro & Star Citizen as well + the 24 Cores I have backhand, so I am not worried for that part likewise.
Nvidia is way too expensive for what they offer, so sorry guys gonna stick with AMD Radeons for now.