I have a serious problem with my Radeon Fury X in Cryengine games when using a 21:9 resolution.
I've tested Crysis 3, StarCitizen and the native Cryengine 3 and 5 so far.
When I play in 1920x1080 window or fullscreen mode, I got 60 FPS in StarCitizen, but when I play in 2560x1080, I get 50 FPS in windowed and only 20 FPS in fullscreen.
Same goes for 3440x1440: 15 FPS in fullscreen and 35 FPS in window mode.
When I use a custom 16:9 resolution like 2560x1440 I get 40 FPS in both, window and fullscreen.
That never happend in any other Game so far. Diablo 3, DayZ, Giana Sisters Twisted Dreams and F1 2011 all running same speed in fullscreen and window mode. Even Doom runs in both modes at 80-100FPS in 3440x1440 Ultra Details.
A friend of mine has the same monitor, using a Nvidia GTX1080, and he got no such problems in Cryengine games in 21:9. So don't tell me that Cryengine then can't handle 21:9 fullscreen...it definitly can! Rest of our hardware is identical btw.
Intel Core i7 4790K
16 GB DDR3
AMD Radeon Fury X
Windows 7 64-Bit HP
AMD Crimson 16.12.2