I have a problem with RSR and my 4k TV, and like the title said, he recognize my TV as a 1080p TV and activate only when I go under 1080p resolution (Like RSR 720p > 1080p).
It work well on my PC monitor LG 27GL850 when I can go to under 1440p resolution to 1440p with RSR, and even If I unplug my monitor and only keep my TV plug on my 5700XT (because i supposed maybe there is a conflict when 2 screens are plugged together), It's the same problem.
When I go to AMD adrenaline and look into the caracteristics on my TV, It tell me It's a 3840 * 2160 screen.
Sorry for my english.