So it's a well-known fact that the EXP GDC (all versions), PE4C (v2.1), PE4H (v2.4) and PE4L (v1.5) use some kind of socketted connection to connect itself to the laptop's mPCIe or EC slot.     This socketted connection usually comes in the form of a physical HDMI or mini-HDMI port, which are notorious for being loose, non-locking connectors. As to why the manufacturers decided to use HDMI/mHDMI, it boggles my mind. They could have used literally any other connector.