I currently use two monitors each configured at 1920 x 1080 (HDMI and DVI connection) and the driver sees a total of 3820 x 2160. But I still plan to use two monitors one in portrait mode at full HD, so if I have to upgrade the graphics card, not a problem.
Will get what other upgrades are needed for it, like high speed HDMI cable, HDMI 2 compliant graphics card, etc. The important thing for now is that the monitor is 4K capable. thanks for the heads up.