Dell P2723DE 27" 1440p USB Type-C Hub Monitor - Manual (Page 73)

Operating the monitor │ 73
OSD warning messages
When the monitor does not support a particular resolution mode, you will see the
following message:
2560x1440,
This means that the monitor cannot synchronize with the signal that it is receiving
from the computer. See
monitor specifications for the Horizontal and Vertical
frequency ranges addressable by this monitor. Recommended mode is 2560 x
1440 .
You will see the following message before the DDC/CI function is disabled: