Monitor 3840x2160 works but have to unplug

[MaxJTihomirov]

Hey!
I have Philips monitor with 3840x2160 solution (2xDP, 2xHDMI)

Sierra 10.12.6 clover i7 4790K GTX780 thinks what he is iMac 14.2 everything is cool BUT
I have to start computer using hdmi, after started OS i unplug it and plug DP and this is the only way i can get 3840х2180 in System Preferences. If i start it without unpluging (hdmi or DP) i can get only 1080p.

SO if something goes wrong i have to
turn off computer->plug again HDMI->start OS->unplug (important to wait 1sec) -> plug DP -> change to 3840x2160 in SP

How can i fix it? I tried to change solution in clover... but nothing
I guess this problem is connected with 14.2 coz it has "integral" monitor

 

[slim.jim]

Do you have to switch cables? Have you tried just turning the monitor off and back on? Have you tried clicking the detect displays button in system prefs?

 

[MaxJTihomirov]

Do you have to switch cables? Have you tried just turning the monitor off and back on? Have you tried clicking the detect displays button in system prefs?

Yes, I have to switch cables (hdmi->dp) then my OS ready only after what i can get 3840x2160



Then i turned off/on it (after my "plug again HDMI->start OS->unplug (important to wait 1sec) -> plug DP -> change to 3840x2160 in SP") 3840x2160 disappeared, ~ 2560х1440 max

 

[MaxJTihomirov]

Sometimes I have to reboot after sleep mode cos it starts sometimes in low solution