How to set up multi display with AMD Graphic Card?
Open AMD Catalyst Control Center, click Common Display Tasks, click Rotate Desktop, select the rotation that you want for each monitor, click Apply. (e.g. select Portrait for VN279QLB multi-display)
Click AMD Eyefinity Multi-Display, click Create Eyefinity Display Group, click Identify All, click Apply.
Select the one for which you want to set up for the main desktop, click Continue.
Select a layout for the display group, click Continue. (e.g. select 3 Display (3x1) for VN279QLB portrait multi-display)
Click Arrange to correct the relative position of the display in your display group.
Follow the direction to select the grid position which corresponds to the physical position of the display, click Done.