I got four Quantum3D AAlchemys 8164 in my rack and i can tell you this babies tear appart any other high end gfx setup nowadays.
http://tdfx.de/pic/mercury_05.JPG
If (and only if) you're playing at 1920x1080.Gigabyte GTX 960 4GB OC edition. As long as no VR set is used, this can do everything Horizons has to offer in full detail at high FPS rate, no lags. More power is always nice but... not needed for this game (unless Oculus seems reasonably priced for you...)