4 GB GTX 1050 Ti or 4gb RX 470?

Solution
I'd go with the RX-470, myself. It is considerably faster, and it will perform better in DX12 and Vulkan games. Not that there are a lot of those yet, but I keep hoping.

Example: I have a Evga GTX 1060 3GB and a Gigabyte RX-470. The 470 is amazing in Doom 2016 (Vulkan API), usually outperforming the otherwise stronger GTX 1060.
I'd go with the RX-470, myself. It is considerably faster, and it will perform better in DX12 and Vulkan games. Not that there are a lot of those yet, but I keep hoping.

Example: I have a Evga GTX 1060 3GB and a Gigabyte RX-470. The 470 is amazing in Doom 2016 (Vulkan API), usually outperforming the otherwise stronger GTX 1060.
 
Solution