Question, why would it require two displayport cables and two outputs from a video card? A displayport 1.4 cable and connection are supposed to support 5K at 60Hz.
Is that a limitation of the driver board?
Is that a limitation of the driver board?
Additional speculation: all 5k displays on the market so far (LG, Dell, Iiyama, ...?) were made as Apple accessories, probably with Thunderbolt ports in mind. Because the market is not that large they might share some components. TB3 only requires DP 1.2, but can carry multiple streams. The expensive LG display includes a TB3 hub that demultiplexes the DisplayPort streams and sends them off to a dual-link DP controller. Less expensive displays leave out the Thunderbolt part and require dual DisplayPort inputs for full resolution.
8bit 4k at 120Hz:
>>> (3840 * 2160 * 24 * 120) / (1000*1000*1000)
23.887872
>>> (5120 * 2880 * 30 * 60) / (1000*1000*1000)
26.54208The UP2715K, only support dual link DP 1.2/HBR2, which was a bit of a PITA on my machine because nvidia's board partners don't always do a good job of describing which ports on the back of the card can be used for dual link.
https://downloads.dell.com/manuals/all-products/esuprt_displ...