I bought the Dell Optiplex 7040 Tower with AMD Radeon R7 350x 4GB (DP 1.2 , DVI), but the 4K Dell Display P2415Q runs ONLY by 30Hz connected to the DP 1.2. Deos this grafic Card Supports ONLY 30Hz? This is very annoyng if 60Hz are not supported.
Displayport 1.2 can do 60Hz at 4K. MST needs to be set to off on that monitor to enable DP 1.2 see page 34 of the manual.
Thank you all