Abstract: Dynamic display output techniques for computing systems and user devices are presented herein. Examples include downstream device-selectable outputs from a user device over a shared connector for HDMI and DisplayPort interfaces. In one example, a method of providing a display output from a user device includes detecting a downstream device communicatively coupled to the user device over a display connector. Responsive to detecting coupling of the downstream device, the method includes sensing a mode selection input by the downstream device through the display connector, and selectively providing at least video output over the display connector compatible with a preferred video interface indicated by the mode selection input.