Dell Precision 5560 External Display Connection Manual page 11

No display or Blank screen after display Multi-Stream
Transport (MST) option is turned off via WD19/WD19TB/
WD19DC series docking stations
Question
When the display Multi-Stream Transport (MST) is tuned OFF via WD19/WD19TB/WD19DC series docking stations, the display
does not power on or has a blank screen.
Cause
Multi-Stream Transport (MST) hub do not have any specific definition for handling or deal with this kind of DisplayPort
Configuration Data (DPCD) change (eg: MST/SST, DP1.4/1.2, HDR, FreeSync).
Workaround
● Hot-Plug Dock cable.
● Hot-Plug Display cable.
4K display cannot reach 4K @60 Hz resolution if it is
connected to a WD19TB series docking station via MFDP
port.
Question
When a 4K display is connected to a WD19TB series docking station via Multi-Function DisplayPort (MFDP) USB Type-C
connection, the display cannot reach 4K @60 Hz resolution.
Cause
According to DP Multi-Stream Transport (MST) DSC spec, DP stream is controlled during the blanking period and the size
of those blanking period gets affected by lot of factors including DSC (display stream compression) reported monitor support
(modes, timings, RB1, RB2) and, Multi-Stream Transport (MST). Due to Intel limitation in this generation, DSC is disabled and
hence it causes limitation with small blanking period. If the blanking period is too small, there will be sufficient bandwidth for 4K
@60 Hz resolution.
Workaround
Use Type-C to DisplayPort (DP) or HDMI dongle to output display as alternative.
Troubleshooting 11