A:Answer The computer comes with a GTX 1060 3GB. It has one each: HDMI, displayport, dvi.
The graphics card is not built in and can be replaced.
Outputs 4k on my monitor and supports my Oculus Rift. Graphics look good and can handle some detail tweaking but more capable cards will offer more options. I don't think the motherboard supports SLI.
In addition, the motherboard also has HDMI and other video ports that work but bypass the graphics card.
You seem mostly interested in dvi.. As far as I understand it, HDMI offers the same or faster speed/larger data bandwidth while including sound and displayport even more so than HDMI.