I have an Early 2015 Retina Macbook Pro 2.7 GHz i5, and it does not work with certain displays.
I first tested it with a display(call it display A) Mini Display Port to DVI cable which did not work. Interestingly enough, when the display was turned off, my Macbook was able to detect the display fine; but when truned on, the Mac was unable to detect the display. When I tried to connect a 2010 Macbook Pro, it worked perfectly.
I tried again with a different monitor(Display B). I had the same issue of my Macbook Pro not being able to identify the display, but a mid-2010 iMac 21.5 was able to connect fine. I tried using both an HDMI-HDMI cable and a mDP-HDMI cable.
I tried again with an HDTV, and using an HDMI-HDMI and a mDP-HDMI cable, and both worked fine for my 2015 Macbook and the 2010 Macbook.
Any ideas as to why my computer only works with certain displays?