I just got my pg279q but i have a problem. I have a secondary monitor ( 1080p 60hz ips Dell S2740L ) and while this one is connected i can't set the pg279q to 144hz, but only to 60hz.
The fun fact is that i see the 144 hz in the dropdown, but if i choose it and press apply with the second monitor plugged in it just turn back to 60hz The moment i disconnect the dell the pg279q goes to 144hz and all it's good.
Plus the secondary monitor has a pinkish color to it . The moment i connect just the one it's perfect white (i use it for years, i used to have 2 Dell S2740L and the pinkish problem is persistent even with a old gtx680). Color calibrating does NOT help. There is not enough color option to change that much pink. http://i.imgur.com/mZwSYnk.jpg
Now i tried to google and search this forum but nothing came up.

Here what i tried so far:
* Using different cables for the dell; tried both dvi and hdmi (only 2 avaible on the display)
* Tried some old driver
* Tried to disable G-Sync and set 144hz. but nothing

For now the only thing that allow me to play at 144 is disconnect the secondary monitor.
I really don't know what can i do. I can live with the pinkish color on the second monitor as long i can use both monitor togheter with the pg279q at 144hz

My specs:
Win 10 64bit, 980ti, driver 358.91 and tried to unistall them and let windows install the default old ones.