Method, apparatus, system for thunderbolt-based display topology for dual graphics systems

A method for switching between an internal graphics card and an external graphics card, the method comprising:

• detecting a connected device at an input port of a ThunderBolt input/output (I/O) controller;
• identifying a graphics processor preference identifier for the connected device;
• determining a graphics processor preference for the connected device based on the graphics processor preference identifier;
• and
• connecting the connected device to one of a first display port or a second display port based on the determined graphics processor preference.

A computing system comprising:

• a processor core comprising an internal graphics processor;
• a graphics board connected to the processor core by a link compliant with a Peripheral Component Interconnect Express (PCIe)-based protocol;
• a ThunderBolt input/output controller subsystem connected to the processor core by a link compliant with the PCIe-based protocol, the ThunderBolt input/output controller subsystem comprising:
• an output port;
• a display port;
• a switch circuit linking the output port to the display port;
• and
• logic to:
• detect a connected device connected to the output port;
• obtaining a graphics processor preference identifier from the connected device;
• and
• instructing the switch circuit to logically couple the connected device to one of the internal graphics processor or the graphics board via the display port based on the determined graphics processor preference.