External Thunderbolt display does not work.

[Equinoxe]

Hello,

I have an Apple Thunderbolt 27-inch external display that I was using with my Macbook Pro without any issues whatsoever.

I recently bought a new HP Elitebook 850 G6 6XD58EA, explicitly looking for a laptop with Thunderbolt compatibility, so I can continue to use my display. My display uses a Thunderbolt 1 connector (Mini DisplayPort), so I bought an adapter from the official Apple retailer that connects Thunderbolt 1 with Thunderbolt 3 / USB-C.

It turned out that when I connect the display nothing happens. No notification from the Thunderbolt centre for a new connected device. The device manager starts to refresh constantly, but does not install any new drivers. When I go into display settings it does not even detect there is a monitor attached.

I have read everything regarding this or similar issues that I found and have done the following tests:

1. Installed the newest video drivers, thunderbolt drivers, thunderbolt firmware, BIOS, windows updates. No change.

2. Installed previous versions of Windows / drivers / BIOS in different combinations. No change.

3. Bought a new adapter (Startech.com #TBT3TBTADAP). Still exactly the same.

4. Got a HP Thunderbolt dock - the dock works, all the other ports work, the display connected to the dock does not.

5. Tinkered with various BIOS options. The only setting that changes the outcome is disabling the Thunderbolt support. After disabling it Windows 10 just detects the adapter connected and nothing else (Driver says Thunderbolt 3 to Thunderbolt 2 adapter)

6. Went to the service centre, explained what tests I did and they actually changed the laptop with a new one, because possibly the Thunderbolt 3 chip in the first one was not working. I re-did everything with the new one to no avail.

7. Downloaded Apple Bootcamp drivers on my Mac and installed them on Win 10. Still nothing.

8. Installed a fresh Win 10 copy with no additional software from the manufacturer, did not change anything as well.

9. Tried changing colour settings and resolutions of the monitor through my Macbook, no effect.

10. Tried installing newer firmware of the display through the Macbook, no effect.

11. Tried connecting first an HDMI display and then the Thunderbolt 3 one (saw it in an obscure article), still does not detect the Thunderbolt one. The HDMI one works.

I have my Macbook Pro next to me while testing new ideas, the monitor is connected and works flawlessly. I know for a fact that Apple Thunderbolt display works with various Win 10 PCs and laptops. This could be verified with a quick Google search.

I have lost around 60 hours reading and doing stuff that does not work. Since I bought this laptop exactly because of the Thunderbolt 3 feature it has turned out to be a major problem. I am not by any means a professional in this domain so I could be missing something really simple.

Can any of you give me any idea what could be the problem?

Thanks.