What kind of cable/connector is this? It looks like an HDMI connector, with very similar pins, but it has a slanted edge on only one side and the other side is square.
What kind of cable looks like HDMI but has only one slanted edge
cableconnectordisplayporthdmi
Related Solutions
Did you already go out and purchase this wall plate? If you did not already buy it, then do NOT purchase that wall plate. Instead, purchase one like this one, as it has an HDMI socket on each side. No wiring. Of course, this still makes me wonder about why you only have one wall plate.
You should be using two wall sockets... the whole purpose of using wall sockets is for a professional installation, and if you are using only one, you kind of defeat that purpose.
But... you want wiring and pinout diagams...
..of course, you could just use two wall plates, and just be consistent between them. The reason why this is going to be difficult?
There is no standard for color-coding the wires and it can become very easy to make a mistake. I think it’s fair to say that you will have a tough time contacting the manufacturer to find the color code for the wiring.
But this article on repairing damaged HDMI cables might come in handy.
In the end... just getting wall plates that don't need to be wired might be the way to go.
So I got a mini display port to HDMI cable + a HDMI to display port adapter. It does not work. It all seems to fit fine, but the monitor is blank.
Because it isn't an "HDMI to DP" adapter, but a "DP++ to HDMI" adapter, which picks (ONLY) the TMDS signal (what HDMI uses) output from a DP++ source to an HDMI sink (e.g. monitor).
So I got a mini display port to HDMI cable
And this is pretty much an DP++ to HDMI "adapter" as well.
So as you could have imagine, your connection is something like this:
(Mac) DP++ --> HDMI|HDMI <-- DP++ (Monitor)
And obviously it's only natural that it won't work.
P.S. IF the mini-DP port of your Mac isn't a DP++ port (though it should be), your mini-DP to HDMI cable won't work either even if you connect the HDMI side directly to an HDMI monitor. In that case you will need an active (i.e. involves signal conversion) mini-DP to HDMI adapter.
Ref.: https://en.wikipedia.org/wiki/DisplayPort#Dual-mode
To convert HDMI/TMDS signal to DP signal "again", you will need an active HDMI to DP adapter (which seems to be rare).
Best Answer
This is a DisplayPort — it's pretty common on desktops and quite a few laptops.