I've got a C-level user who has a Latitude E7450, and E Port Plus docking station, 2 desktop monitors and a large, wall-mounted LCD monitor. The E7450 has an Intel HD 5500 graphics card. What he wants:
Laptop lid closed in the docking station off to the side.
Left-hand desk monitor as the primary.
Right-hand monitor as an extended desktop.
Wall-mounted monitor a clone/duplicate of the primary monitor (he uses it for meetings at his conference table at the other end of his office).
The wall-mount monitor is wired inside the wall to a wall plate with an HDMI connector. It comes with a 6-ft cable with HDMI on one end (plugs to the wall) and DVI-D on the other. He also had a short adpater connected to the DVI end with Display Port on the other which he had plugged into his old HP docking station.
The right-hand monitor is connected with VGA and the left-hand with DVI.
No matter what type of adapters or cables I try in various combinations, I am unable to get it to work as he wants. We replaced his old HP laptop about 3 weeks ago and it worked fine in this scenario. (I didn't think about diagramming how the various cables were connected to his HP docking station.) The HP used a DMS-59 connector for the left-hand (primary) monitor.
Some research on a Spiceworks forum lead me to think that my problem is both a display resolution issue (I understand that they should be identical, if possible), and a connection problem. I had my supervisor get me a DVI splitter so I could take one output (FROM the docking station) and send it to 2 DVI sources. Can't get the laptop to detect the monitors at all. Tried on a different laptop, same model, and same result. I was sent a link to a Dell KB article, "How to configure three (3) displays on a Dell Latitude Portable with Intel HD 4x00 Graphics" http://www.dell.com/support/article/us/en/04/SLN115952/en and I see that DVI has it's limitations with both Intel HD 4x00 and 5x00 graphics cards, but it could be done. I also saw an article about using Display Port 1.2 in a "daisy-chain" to support 3 or more monitors. (search using "[DisplayPort Quick Guide] Daisy Chaining 2 to 4 Monitors" as the search term).
My question to everyone is this: what do you recommend, and why? I need something I can take to my supervisor as "the" answer.