2560x1440 output is only available when a single HDMI monitor is connected to the dock, and requires a “High Speed” HDMI cable. 2560x1440 mode will operate at a 50Hz refresh rate; all lower modes support 60Hz refresh rate.
2560x1440 output requires current DisplayLink drivers and the attached monitor must natively support 2560x1440 via HDMI input.
Note: Most monitors that support 2560x1600 do not support 2560x1440.