Firepro w5100 connected to Dell P2415Q using displayport 1.2 cable, on a Precision T7600.
It only gives 30 hz as an option under 4k resolution. 60 hz is grayed out and is not an option above 1080p.
What is the "weak link" keeping that it from supporting a full 60 hz?
Make sure W5100 is installed on blue PCIE slot. Check your display settings and make sure it is set to DP 1.2