Wacom, purveyors of fine ... [Bumhee] wanted a Cintiq, but didn’t want to pay the Cintiq price, leading him to install a display in his old Intuos tablet. It’s an amazingly simple build ...

In the case of the 2015-vintage Wacom Cintiq Companion 2, this turns out to be the so-called Athena chip, which switches the display input between the HDMI port and internal display controller.