I can't reach 4k 120Hz using DP kabel 1.4 (32Gbps) paired with MSI RX470 4GB Gaming X. When my monitor is in DP 1.2 mode I have just 4k 60Hz, but when I change is to DP 1.4 my monitor (in monitor settings) turns off/ goes black screen. I have tried 2 cables, the one Samsung gave me with monitor...