Lost 4k option?

[wez130]

Hi, i've been running my system fine with 3840x2160 resolution since yesterday, just downloaded assassins creed and played it in a different resolution (2440 or something @60hz), exited the game and now i can't change back to 4k. (Asus ROG 1080ti / Philips 43" 4k monitor). The max resolution i can choose in display properties now is 2560x1440

Any ideas?

 

[wez130]

Fixed, my monitor switced to display port 1.1 mode, reverted back to 1.2 and it's sorted. Thx