None of the AMD catalyst 14.4 and 14.7beta can deliver reliable 4K60 SST with the R7 265 GPU to Asus PB287Q.
The monitor is correctly configured for DP1.2.
Symptoms: flickering, black screen for some seconds, noise on displays speaker, also disturbed pixels - all mixed over time with a sharp display inbetween. The display is troubled for about 1 to 20 times per minute, giving around 55 seconds of full function and 5s in sum with errors mentioned before.
As it turned out at overclockers.net and other forums it is mainly a drivers issue.
Please, AMD, fix this issue!
The cards was bought because it was promised (by AMD) to support 4K60 SST and we simply want to stick with AMD but are now very disappointed and think about a turn to Nvidia.
Monitor: ASUS PB287Q
GPU: Sapphire R7 265 Dual-X 2GB DDR5
Cable: stock Asus shipped with monitor, delock premium 2M display port.