External Display recognized as DisplayPort, but connected via adapter using HDMI I'm trying to connect a brand new macbook Pro with 2 USB-C using an adapter with HDMI. The macbook detects the display, but the Connection Type is DisplayPort. Is there a way to change it? Screen displays the message "No HDMI signal detected"

  Chipset Model:    Intel Iris Plus Graphics 640
  Type: GPU
  Bus:  Built-In
  VRAM (Dynamic, Max):  1536 MB
  Vendor:   Intel
  Device ID:    0x5926
  Revision ID:  0x0006
  Metal:    Supported, feature set macOS GPUFamily2 v1
  Displays:
Colour LCD:
  Display Type: Built-In Retina LCD
  Resolution:   2560x1600 Retina
  Framebuffer Depth:    24-Bit Colour (ARGB8888)
  Main Display: Yes
  Mirror:   Off
  Online:   Yes
  Rotation: Supported
  Automatically Adjust Brightness:  No
DELL U2917W:
  Resolution:   2560x1080 (UW-UXGA - Ultra Wide - Ultra Extended Graphics Array)
  UI Looks like:    2560 x 1080 @ 60 Hz
  Framebuffer Depth:    30-Bit Colour (ARGB2101010)
  Display Serial Number:    749DX73N346L
  Mirror:   Off
  Online:   Yes
  Rotation: Supported
  Automatically Adjust Brightness:  No
  Connection Type:  DisplayPort  # I believe this is the problem.
The system is reporting that your Dell monitor is connected via DisplayPort be because you're actually connected to the DisplayPort port.  That said, it's not what's causing the problem you're describing.

What you're doing is converting the signal from DisplayPort (DP) to HDMI and most likely using a passive adapter; what you need is an active adapter or better still, just go from DisplayPort to DisplayPort (that monitor supports it).

I describe this in further detail in these posts:  


External monitors show blank screen until restart
MacBook Pro detects syncmaster (monitor) but doesn&#39;t display
USB-C to Displayport cable or adapter