Hey all, I recently got a new laptop, dock, and monitors at work and am having issues with the 3rd monitor. Model are as follows:
1 - Dell Latitude 7480
1 - Dell D6000 Dock (2 Displayports, 1 HDMI port)
3 - Dell E2318H Monitors (Displayport and VGA input only)
The D6000 dock has 2 display port ports, as well as 1 HDMI. I can run 2 of the monitors successfully on the displayports, but cannot find a cable that will allow me to use the 3rd monitor with the HDMI port. I have tried restarting multiple times with lid closed, and also rebooting the dock by disconnecting the power.
I have tried both of these with no success:
HDMI to Displayport cable.
HDMI to active VGA adapter to VGA cable. (Adapter is a Startech HD2VGAE2)
FYI, when using the dock with an HDMI to DVI cable and older monitor, it recognizes the 3rd monitor correctly after rebooting the dock.
HDMI to DisplayPort only works when the source uses DisplayPort and the display uses HDMI; it does not work in the opposite direction.
An active HDMI to VGA adapter should work, but I've seen some of those adapters receive updated chipsets because apparently it's a bit finicky -- although even after solving any problems there, you're still left with analog video, which looks noticeably worse than digital video especially at 1080p.
Have you looked into whether the D6000 supports DisplayPort MST? If so, you could connect a DisplayPort MST hub to one of the D6000's outputs and connect multiple displays to that hub.
Otherwise, maybe get a better display with more flexible input options or a better dock. The WD15 and TB16 are both compatible with the 7480 (although you'd need the TB16 to support triple displays), and they include a native VGA output. And unlike the D6000, those docks tap into native GPU outputs wired to into the system's USB-C/Thunderbolt port rather than using a DisplayLink chip to handle video output. DisplayLink has several disadvantages over using displays driven directly by the GPU, but the D6000 uses it because that's how it maintains compatibility with systems that only have USB-A connectors. Theoretically it could have been designed so that systems that connected over USB-C used the native GPU output, but it wasn't; instead, it uses DisplayLink all the time.